Citations Online
Preliminary Guide for Content Providers


This guide presents an easy-to-use citation architecture that promotes credibility assessment for online documents.

Online documents have an uncertain degree of credibility, violate traditional conventions of the ink-and-paper world, and are subject to revision, replacement, and deletion. Credibility assessment is essential.

Each reference contains three elements that speak to credibility. The contributor element emphasizes information suggestive of author credibility. The reference's publishing element emphasizes what publishers do. The date element allows the reader to see whether a web document has changed since it was cited.

Regarding ease of use, the approach taken is for providers of online content to write citations and references in a convenient format. Their writings are then transformed in real-time to a reader's view that is convenient to read.

In the reader's view, each citation is hyperlinked to its corresponding reference. The citation is equipped with a mouseover note that displays its corresponding reference whenever the mouse pauses over the citation. The reference is automatically annotated with an icon that adds visual appeal.

This guide is based on research presented in Citations Online: Architecture Development. The research shows how the Citations Online architecture stems from 28 identified communication needs.

Omitted Guidance  

Choosing a consistent style is essential for readability, but there are cases where the particular choice is not important. Consider dates, for example. Some authors prefer the conventional "month dd, yyyy" format, while others may prefer the IEEE "yyyy-mm-dd" format.

There are no required abbreviations. This convention differs from the ink-and-paper world, where there is a need to conserve paper. As an example, the JASIST might be better expressed as the Journal of the Association for Information Science and Technology.

Capitalizing the first letter of principal words in a title is a pleasant option consistent with AP guidance[ap-guide]. For example, John Berendt's Midnight in the Garden of Good and Evil[jim].


An online document is a human-readable document with an advertised URL. It is a document that other online documents can link to. Some or all of an online document's pages may be restricted, for example, by placing them behind a paywall. This guide is about citations and references in online documents.

A document that isn't online is said to be offline. Print documents are offline. eBooks, though available online, are offline because they do not have advertised URLs that can be linked to.

Contributors are people involved in the creation, presentation, and maintenance of content, including any research involved in creating content. Contributors are conveniently divided into content providers and secondary contributors. Authors are content providers who accept responsibility for content.

In this guide, the citing document is the work whose citations and references are under discussion. The citations (in-text citations) occur in the citing document's main text, and its references occur in its reference section (works cited section).

Each citation points to a reference that in turn points to cited content. The same content can have multiple presentations. They can appear in several different places and in multiple formats. They can appear in multiple languages. They can appear both online and offline. Typically, the cited content occurs on a web page that also contains uncited content.

The format of a citation or reference differs between contributors and readers. There is a provider format for providers, a reader's view for readers, and a provider-to-reader transformation that converts one to the other.

This guide is mainly about the provider format. Examples are given in this format, but with a button to press to see the transformed reader's view.

Provider Citations  

Citations can point to references in one of two ways.

A root citation identifies content that, within the context of the citing document, is not part of some larger cited body of work.

A subsidiary citation identifies content that is logically subsidiary to content that is identified by a root citation.

The organization of cited content into root content and subsidiary content is performed at the discretion of the content providers. The subsidiary content may be found in a section of the cited root document, another document, or a section of another document. The subsidiary document may have an unrelated URL.

A provider root citation has the form \[root], where the root identifier is chosen at the convenience of the content provider. A provider subsidiary citation has the form \[root, part-name], where the part-name is a short name for the subsidiary content. To prevent a bracketed passage from being treated as a citation, escape its left bracket with a back slash, like so: \\[ protected passage ].

The provider-to-reader transformation transforms each citation into the form " † ", where the dagger anchors a hyperlink to a corresponding reference and its associated mouseover note.

A citation documents an idea by pointing to a supporting cited work. Suppose there is a further intent to acknowledge or give credit to an author. In this case, an annotated citation is needed because all citations look alike in the reader's view. Consider the following example:

I cannot tell a lie… I did cut it with my hatchet.
       — attributed to George Washington by Parson Weems[George]

Provider References  

The citing document's reference section is a list of references. Each reference is a paragraph. References may be listed in any order because the provider-to-reader transformation sorts them.

The transformation algorithm sorts root references according to their citations' order of occurrence in the main text. Under each root reference, the algorithm gathers related subsidiary references and sorts them according to their titles. The sorting process has the effect of organizing the reference section into segments with each segment headed by a root reference. Numbered subsidiary titles sort properly, as in the following example:

9.8 Format of the Author Element

9.10 Identification of Specialized Roles

Reference Structure

In the reader's view, a reference has five reference elements. In the provider format, each reference also has a reference identifier and, in the case of a root reference, an optional indicated icon.

The reference design extends the format used by search engines in that the first two core elements are the title and links to the referenced work. Very briefly, the elements of a root reference are,

Each reference element ends with sentence-ending punctuation followed by white space. If a period, question mark, or exclamation point followed by white space is necessary inside a particular reference element, escape it with a backslash. For example, "Yo\! Yes?" transforms to Chris Raschka's story, Yo! Yes?[yo-yes] This approach to punctuating references suggests avoiding unnecessary periods — for example, using J R R Tolkien instead of J. R. R. Tolkien.

Here are some citations and accompanying references — a root reference and two subsidiary references. Press the blue button to see how they are transformed and hyperlinked.


The story about the young George Washington and the cherry tree is generally thought to be apocryphal[George]. However, it has found its way into everything from children's stories[George, child] to serious artwork[George, cherry].


icon icons/cherryTree.png. George. Cherry Tree Myth. Article. Jay Richardson (author). undated.

George, cherry. Cherry Tree. Oil on canvas; explanation, video. Grant Wood (bio). Amon Carter Museum of American Art. Created 1939.

George, child. Childhood Stories of George Washington. PDF file, pages 3-6. Harriet G Reiter (story teller), Katherine Follett (editor), Tad Butler (illustrator). Reading A-Z. 1906.

Example 1. Root and Subsidiary Citations

Reference Elements

Let us now consider each of the seven elements. After that, we will take up some additional considerations that apply to subsidiary references.

Favicon for Root Citations

By default, the algorithm gets the icon from the reference's first linked web page. This default can be overridden by explicitly specifying the icon, like this: icon image-path. The algorithm then uses the provided image path.

In the following examples, the top three icons were automatically scraped from well-known websites, and the bottom three are contributor-provided.



Reference Identifier

Reference identifiers are modeled directly after the citations. For example, the reference identifier for the citation \[George, cherry] is George, cherry. None of this shows in the reader's view. The format transformation changes the citation to a hyperlinked dagger and buries the reference identifier in the HTML source.

Title Element

Provide a preferred title, an optional alternate title, any needed title appendages, and optional title clarifications.

A reference can have more than one title. If the title is in a foreign language there is both the foreign title and a translated title. For the sake of reader convenience, when there are two titles, the first title should be the one readers are more likely to appreciate. The alternate title is set off with parentheses.

A title appendage is anything needed to clarify which document the title refers to. For example, version, volume, issue, build, release, edition, supplement. The title appendage follows the title. It is set off by a comma or semicolon as appropriate.

A title clarification is set off with square brackets. Common clarifications include, a book review, clinical trial, consensus document, exposition, large-scale study, literature review, and news article. In the provider version of the reference, the title clarification is not preceded by a backslash because the reference section is not parsed for citations.

The provider-to-reader transformation italicizes the titles of root references by default. An author who wishes to override the default can do so by making explicit use of italics. The use of italics in titles is essentially a matter of taste.

The title element can turn up in various places. Typically, it is on a web page's face. Often, it is in the page's HTML source, in the <title> element. These titles may be different, in which case the one on the document face is probably more accurate. In the rare case where a page has no title, make up a titular description and wrap it in parentheses. Alternatively, use the first few words of the referenced document and enclose them in quotes.

Title examples

Consider the following title elements given in the provider format:

Yo\! Yes?, multiple editions[yo-yes]
Macbeth (The Tragedy of Macbeth)[macbeth]
Multiple Book URLs (Box 67 Multiple URLs)[NLM, box-67]
The Analects \[of Confucius] (论语)[secret]

The story Yo! Yes? illustrates the distinction between content and presentation. It is a single illustrated story that has been presented in 21 editions. To see the 21 editions, follow the appendage hyperlink.

The second and third titles show that the need for alternate titles isn't just due to language barriers. The Analects has been pre-italicized to keep the format transformation from italicizing the following Chinese title.

Here are three more examples:

After the Season \[in The Poem Tree anthology][season]
Badlands \[review of the film Badlands by Terrence Malick][badlands]
"'What's to-day, my fine fellow?' said Scrooge"[dickens, Christmas]

These titles illustrate the following:

a title clarified by reference to a containing anthology
a film review clarified by mention of the film reviewed
a quoted passage used as the title of a subsidiary reference

Provide a list of one or more links to representations of the referenced content.

The representations are of two kinds: presentations of referenced content and portrayals of related information. A link's clickable anchor is responsible for distinguishing between presentations and portrayals.

Anchors for presentations include article, blog post, conversation, email, English translation, online book, painting, and PDF file. Anchors for portrayals include abstract, comment, commentary, errata, related text, review, and vendor.

Put presentations before portrayals. Put more credible representations before less credible representations. For added clarity, presentations are separated from portrayals by a semicolon if both are present.

Try to choose URLs that qualify as permalinks.

To get the permalink for a Facebook post, click on the post's date. The permalink will appear in the browser's address bar.

To get the permalink for a Twitter tweet, click on the tweet. To get the permalink for an Instagram picture or video, click on that.

Translate a DOI (Document Object Identifier) to a permalink by prefixing '' to the DOI.

If a reference has no hyperlinks, use "unlinked" for the link element. The provider-to-reader transformation sets such references in a gray color.

Links for Online Documents

An online presentation link is a hyperlink that goes directly to an online presentation of the referenced content.

Consider the Cherry Tree reference in Example 1. Its first link, Oil on canvas, goes to a digitized presentation of a painting. In addition, this reference also has two portrayal links, namely explanation and video.

A presentation link to a linkable fragment in a containing online document uses a fragment URL. Consider the the reference,

Classification \[of lung cancers]. Article section. WikiProject Medicine (supervising project). Wikipedia. Updated 2021 September 28[lung-cancer]

The link's fragment URL is

For a subsidiary reference to a non-linkable portion of an online document, the link target is a containing portion that does have a link. Consider the reference,

"'What's to-day, my fine fellow?' said Scrooge". Page 110. ~. ~. ~[dickens, Christmas].

Page 110 contains the referenced subsidiary fragment; the page number is given relative to its containing root document.

Here is an example of a subsidiary reference from Example 1 that is not for a portion of the root document:

George, child. Childhood Stories of George Washington. PDF file, pages 3-6. Harriet G Reiter (story teller), Katherine Follett (editor), Tad Butler (illustrator). Reading A-Z. 1906.

The subsidiary link, PDF file, pages 3-6, includes a description of the root document namely "PDf file."

Links for Offline Documents

The links for an offline document describe offline presentations and online portrayals such as an available vendor, synopsis, or review. Consider the following example,

Midnight in the Garden of Good and Evil. eBook, vendor, book review, synopsis. John Berendt (bio). Random House. Published 1994 January 13[jim].

In this reference, vendor, book review, and synopsis are online portrayals. "eBook" is an optional offline link; think of it as a presentation link with a missing URL.

For a subsidiary reference to a portion of an offline document, the first offline link specifies the portion. Consider the following example:

9.4 Four Elements of a Reference. Page 283; APA article. ~. ~. ~[APA, elements].

The first link, Page 283, is offline. It points to the page containing the APA guide's Section 9.4. The second, APA article, is an online link to a portrayal of the content of Section 9.4.

Contributor Element

List key contributors with authors and content providers listed first. A contributor's name may include honorific titles, for example, LCSW, RN, MD, PhD, librarian. A contributor can be an individual, a group, or an organization.

The number of contributors to list depends on the likely audience for the citing document. For example, if the potential audience consists mainly of authors of the referenced works, list as many content providers as possible. When not listing all contributors, end the contributor element with "and others" or "et al." If no person or organization acknowledges responsibility for creating the work's content, use "unattributed" for the contributor element.

In the case of a group author, list the group's leaders, if available. The same goes for organizational authors.

Each contributor's name is optionally followed by a parenthesized list of credibility-related attributes such as the contributor's role, author bio, or organizational affiliation. The roles are given first and are separated from other credibility attributes by a semicolon.

Give enough role information to distinguish content providers from other contributors. The default role is "author." An included biography, history, or about page can be given using a hyperlink. If a contributor is provided as a Twitter handle, link it to the associated Twitter account.

Here is a list of common contributor roles[cr, MLA] [cr, casrai] [cr, IOPScience] [cr, ICMJE] [cr, Childers] [cr, patents] [schema, roles] [schema, honorific-suffix] [schema].

Content Providers

article or web page writer


conceptualization — identifying goals and objectives


construction of test equipment

coordinator — pre-publication review, interaction with publishers, and site managers, signoff by authors and other stakeholders, issue resolution


data acquisition and curation

data analysis and interpretation


initial content creation in articles

initial content creation in movies or comics

investigation — performing experiments, gathering evidence

maintenance — identifying and publishing corrections

methodology development — identification of previous relevant work, experimental design, development of predictive models

presentation, for example, at conferences

producer/editor — leader

review and revision

script/story writer

software development

validation — ensuring results are reproducible and do not contain unexpected inconsistencies with previous results

visual storytelling — in movies or comics

writing the initial draft

Secondary Contributors

care of study participants

consulting or advising

funding acquisition

host —  as in TV show host

key grip — supervises lighting and rigging crews

language editing

lighting/inking  — controls lights and shadows, uses color to convey depth, mood, tone, and emotion in films and comics



physical resource acquisition — provision of study materials, reagents, patients, laboratory samples, animals, instrumentation, computing resources, or analysis tools


sound/letterer — in comics, the sound is conveyed through a letterer's word balloons.

supervision — oversight and leadership for activities including planning, execution, and mentorship

visualization — research presentation

web mastering

Some contributors with associated credibility data:

Matthew Childers (author, illustrator, writer; bio)[cr, Childers]
 —  a contributor with multiple roles and a biography

Liz Allen (co-chair), Alison McGonagle-O’Connell (co-chair)[cr, casrai]
 —  a group author with a named leadership

WikiProject Medicine (supervising project)[lung-cancer]
 —  a group author with an identified leadership

American Psychological Association (about)[APA]
 —  a corporate author with an about page

Publishing Element

Give the organization or organizations involved in publishing activities such as review, acceptance, final editing, marketing, and distribution to an intended audience. Likely examples include traditional publishers or their independently operating imprints, newspapers, journals, and websites. In each case, the title of the publishing entity suffices. If a work was published before 1900, include the publisher's city. In many cases, the cited content is contemporary with the web page on which it appears, and the likely publisher is the page's website. A website's title is the title of its home page.

If there are several publishers, use the publishers of the first link in the link element or use 'multiple publishers' for the publishing element.

A web page's publisher will often appear at the top of the web page along with the publisher's logo. Alternatively, it may appear in the page source, often in the title element.

Some publishers:

Globe Theatre[macbeth]
 —  a publisher of live performances

Colorado Department of Health and Environment[ap-guide]
 —  an organizational publisher[George]
 —  a website explicitly listed as the publisher

British Journal of Pharmacology[russo]
 —  a journal

 —  an author as the publisher

 —  a posting platform

Date Element

Say how and when the content was created or placed online. Regarding how, there are several possibilities:

Posted: Posted without significant publishing activities.

Published: Established as part of a publishing process.

Updated: Modified and reposted.

Use of the choice "posted" implies that the publisher listed in the reference has not performed all of the normal publishing activities.

It is acceptable to use more than one of the above choices. For example, a document may have been posted online before being officially published. In the event that content has both online and offline publication dates, the earlier date is more appropriate.

There are several dates that are typically not included in a reference because they are not properties of the cited content: a document review date, dates of comments on the cited content, the date on which a content provider last accessed the cited content, the date on which a website posted the content.

For non-document materials, the word "created" may be appropriate. If using a copyright date, the word "copyright" is appropriate. Copyright dates are inaccurate estimates of publication or posting dates.

Finding the date may require some detective work. The date may appear prominently on the face of a web page. However, the date may appear only in the page's HTML source code: Search for "date". Some HTML editors will automatically include, in the page's source, the date the page was saved. If no suitable date can be found, use "undated" or "no date" for the date element.

The date needs to be in a format that makes sense for an international audience. For example, 4/3/21 is ambiguous. In some countries, it means April 3, 2021, and in others, it means March 4, 2021.

Some publication dates:

Posted 2014 August 10[monkey]
 —  for a meme posted without significant publishing activity

Published 1911[dickens]
 —  for an online book with a pre-Internet publication date

Performed 1606, second Arden series published 1997 January 31[macbeth]
 — for  a work with many publication dates

Published 2019 October 1, copyright 2020[APA]
 —  for a work published prior to obtaining a copyright

Published 2007, updated 2020 August 5[NLM]
 —  an update date based on posted change logs

Subsidiary References

Subsidiary references are like root references but with a few key differences.

A subsidiary reference omits the page icon, partly due to overall paragraph organization.

Subsidiary references may omit redundant information.

References may be subsidiary to a concept rather than another reference.

Redundant Information

Because subsidiary references are attached to a corresponding root reference by the provider-to-reader transformation, it may improve readability of the reference section to use tildes in place of information that appears already in the root reference, as in the following example.


In understanding the fate of Achilles[twar, fate], it is perhaps best to begin with the Trojan War itself[twar] and the role Achilles played in it[twar, profile].


twar, fate. The Fate of Achilles. Article section. ~. ~. ~.

twar, profile. Profile of the Greek Hero Achilles of the Trojan War. Article. N S Gill (bio). ThoughtCo. 2021 February 16.

twar. The Narrative of the Trojan War. Article section. (editors). A&E Television Networks. Updated 2019 September 11.

Example 2. Subsidiary Reference Ellipsis

In the reference section, root references provide needed context for subsidiary references. The mouseover notes in the main text also provide this context by including the favicon and title of the corresponding root reference in the note for the subsidiary reference.

Reference Segment Titles

The organization of references into segments is further supported by allowing reference segment titles. These consist simply of a root identifier and a title. Optionally, a segment title may be provided with a favicon in the same way as with references. Here is an example.


It appears that Kings Island has no Centaurs[ki, kings]. How come? Hagrid's Magical Creatures has them[ki, Hagrid]. They're not hard to feed[ki, diet]. They're awesome!


icon icons/centaur.png. ki. Centaurs for Kings Island?

ki, Hagrid. Hagrid’s Magical Creatures: First Look at Centaurs for Hagrid’s Magical Creatures Motorbike Adventure. Article. Brittani Tuttle. Attractions Magazine. 2019 April 18.

ki, diet. So How Does a Centaur Eat, Anyway? Article. Judith Tarr. TOR.COM. 2017 April 3 11:00 am.

ki, kings. Kings Island. Fan page. Unattributed. Fan First Global Media. undated.

Example 3. Segment Titles

Provider-to-Reader Transformation  

As already mentioned, the transformation algorithm hyperlinks each citation to its corresponding reference and adds a mouseover note containing the reference.

The algorithm sorts the transformed root references into ascending order according to their citation numbers. The subsidiary references with a given root are collected under the root reference and sorted by title.

In the transformed reference section, titles of root references are italicized by default.

The last step in the transformation is to check that each reference has the correct number of elements and is the target of an in-text citation. Also, that each citation links to precisely one reference. Passing this last check ensures that the entire reference section can be proofread while mousing over the citation daggers to ensure they are correct.

Required Document Structure  

In the citing document, the References heading separates the main text from the reference section and also shows where these entities fit into the overall document structure. A typical document structure is depicted below. The initial and final portions are separated from the main text and reference section that are to be transformed. The reference section does not include any following sections that may be present. Epigraphic material preceding the main heading may include citations. The References heading may be tagged with any of the tags H1 through H6. The leading and trailing content is not processed by the algorithm.

<div...> leading
<p>epigraph</p> <h*>main heading</h*> ... <h*>References*</h*> ... <h*>following</h*>..

Copy the following scripts and style sheet into the header, adjusting for location:

<script type='text/javascript' src="scripts/menus.js"></script>
<script type='text/javascript' src="scripts/mousepoint.0.5.js"></script>
<script type='text/javascript' src="scripts/transformText.js"></script>
<script type='text/javascript' src="scripts/transformRef.js"></script>
<script type='text/javascript' src="scripts/sortAndPolishRefs.js"></script>
<script type='text/javascript' src="scripts/providerToReader.js"></script>
<link rel="stylesheet" type="text/css" href="styles/providerToReader.css">

Add the following script to the end of the page:

(any scripts that handle event listeners)

Implementation Notes  

Diagnostic Messages

The provider-to-reader transformation counts periods in a reference and reports a wrong count by appending one of these messages:

Reference has n missing element(s).
Reference has n too many element(s).

The count can be wrong for trivial reasons. The algorithm looks in the HTML source for periods followed by spaces. That doesn't work if there is a period whose HTML source surreptitiously looks like this: <i>.</i>. Another example occurs when the period following a link is included in the link itself.

If a citation doesn't have an associated reference, the transformation algorithm adds an error reference in one of these forms:

Missing reference for \[root]
Missing reference for \[root, part-name]

If two or more references have the same reference id, each reference is appended with the appropriate message:

\[root] cites duplicate references
\[root, part-name] cites duplicate references

If no citation cites a given reference, that is announced with

\[identifier] citation not found

Protected Passages in the Main Text

It is possible to prevent the provider-to-reader transformation from processing certain portions of the main text. A bracketed passage can be protected by escaping its left bracket, like so: \\[ protected passage ]. Larger portions can be protected by wrapping them in a div, like this:

<div class="skip-transform">
        ∙  ∙  ∙  ∙  ∙  ∙

Known Bugs

The mouseover notes don't work correctly on handheld devices.

If there is a <div> tag hiding in the HTML source of the main text, the provider-to-reader transformation will think that that is the start of the main text. The symptom is that citations before the <div> don't get processed.

As mentioned above, if there is a period in a reference whose HTML source surreptitiously looks like this: <i>.</i>, the transformation will say that the reference has too few elements. Another example occurs when the period following a link is included in the link itself. The HTML source looks like .</a> when it should look like </a>. Yet another example occurs with escaped brackets. If the HTML source looks like this: \</em>\[<em> instead of this: </em>\\[<em>, the transformation tries to treat the bracketed passage as a citation.

HTML comments work correctly when applied to an entire paragraph but not if applied to a portion of a paragraph.

based on the Citations Online reference architecture

cr, casrai. CRediT — Contributor Roles Taxonomy. Original article, NISO presentation, Cell Press PDF summary, Elsevier summary. Liz Allen (cochair), Alison McGonagle-O’Connell (cochair). Updated 2020 April 3.

icon icons/cherryTree.png. George. Cherry Tree Myth. Article. Jay Richardson (author). undated.

schema. Welcome to Proposed standards. Multiple corporate contributors. Updated 2021 July 7.

schema, roles. Role: A Type. Web page. ~. ~. ~.

schema, honorific-suffix. honorificSuffix: A Property. Web page. ~. ~. ~.

cr, ICMJE. Defining the Role of Authors and Contributors. Recommendation. International Committee of Medical Journal Editors. Undated.

jim. Midnight in the Garden of Good and Evil. Kindle eBook; vendor, book review, synopsis. John Berendt (bio). Random House. Published 1994 January 13.

russo. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects [literature review]. Article, PDF version. Ethan B Russo, MD (bio). British Journal of Pharmacology. Published 2011 August.

monkey. "I am who I am". Post. Post Planner. Facebook. Posted 2014 August 10.

cr, MLA. MLA Handbook 9th. Kindle eBook. The Modern Language Association of America. Self-published. Published 2021 April 22.

cr, patents. Patent Basics. Introduction. Unattributed. United States Patent Office. Undated.

cr, IOPScience. Author roles and responsibilities. Opinion. Unattributed. IOP Science. Undated.

cr, Childers. Different Roles in Comic Books. Resource. Matthew Childers (author, illustrator, writer; bio). Updated 2020 November 4.

yo-yes. Yo\! Yes?, multiple editions. Boardbook, hardcover, review. Chris Raschka (author, illustrator; bio). Multiple publishers. Published 1993 March 1 through 2020 April 21.

ap-guide. Associated Press Style: Quick Reference Guide. PDF file. Unattributed. Colorado Department of Health and Environment. Undated.

icon icons/dickens.png. dickens. A Christmas Carol. Online book. Charles Dickens (bio). Hodder and Stoughton. Published 1911.

dickens, Christmas. "'What's to-day, my fine fellow?' said Scrooge ...". Page 110. ~. ~. ~.

macbeth. Macbeth (The Tragedy of Macbeth). Play script. William Shakespeare (bio), Kenneth Muir (editor). Globe Theatre, London; Arden Shakespeare. Performed 1606, second Arden series published 1997 January 31.

lung-cancer. Classification [of lung cancers]. Article section. WikiProject Medicine (supervising project). Wikipedia. Updated 2021 September 28.

badlands. Badlands [review of the film Badlands by Terrence Malick]. Article. Peter Bradshaw (@PeterBradshaw1). The Guardian. Published 2008 August 28.

secret. The Analects [of Confucius] (论语). Chinese and English text.  Disciples of Confucius, James Legge (translator). Chinese Text Project. Written 475–221 BC, translated 1861.

APA. APA Style Guide (Publication Manual of the American Psychological Association, 7th edition). eBook; vendors. American Psychological Association (about). Self-published. Published 2019 October 1, copyright 2020.

APA, elements. 9.4 Four Elements of a Reference. Page 283; APA article. ~. ~. ~.

NLM. NLM Style Guide (Citing Medicine, 2nd edition: the NLM style guide for authors, editors, and publishers). Open-access online book. Karen Patrias, Dan Wendling (technical editor). National Library of Medicine (US). Published 2007, updated 2020 August 5.

NLM, box-67. Multiple Book URLs (Box 67 Multiple URLs). Chapter 22 breakout. ~. ~. ~.

icon icons/contributor-roles.png. cr. Contributor Roles.

icon icons/globeIcon.png. season. After the Season [in The Poem Tree anthology]. Poem. Kate Light (bio). Copyright 1997.