APA style (7th Edition): Reference

The reference list provides a reliable way for readers to identify and locate the works cited in a paper. APA Style papers generally include reference lists, not bibliographies.

In general, each work cited in the text must appear in the reference list, and each work in the reference list must be cited in the text. Check your work carefully before submitting your manuscript or course assignment to ensure no works cited in the text are missing from the reference list and vice versa, with only the following exceptions.

Works excluded from a reference list

There are a few kinds of works that are not included in a reference list. Usually a work is not included because readers cannot recover it or because the mention is so broad that readers do not need a reference list entry to understand the use.

• Personal communications such as emails, phone calls, or text messages are cited in the text only, not in the reference list, because readers cannot retrieve personal communications.
• General mentions of whole websites, whole periodicals, and common software and apps in the text do not require in-text citations or reference list entries because the use is broad and the source is familiar.
• The source of an epigraph does not usually appear in the reference list unless the work is a scholarly book or journal. For example, if you open the paper with an inspirational quotation by a famous person, the source of the quotation does not appear in the reference list because the quotation is meant to set the stage for the work, not substantiate a key point.
• Quotations from research participants in a study you conducted can be presented and discussed in the text but do not need citations or reference list entries. Citations and reference list entries are not necessary because the quotations are part of your original research. They could also compromise participants’ confidentiality, which is an ethical violation.

References included in a meta-analysis, which are marked with an asterisk in the reference list, may be cited in the text (or not) at the author’s discretion. This exception is relevant only to authors who are conducting a meta-analysis.

Reference list entries include the four elements of the author, date, title, and source.

This page describes each element in detail:

• the author element, including the format of individual author names and of group author names
• the date element, including the format of the date and how to include retrieval dates
• the title element, including the format of the title and how to include bracketed descriptions
• the source element, including the format of the source and how to include database information

View the reference examples to see the elements of reference list entries in action.

A summary of this guidance is presented on the page about the basic principles of reference list entries.

If a work does not have an author, date, title, or source, visit the page on how to adjust reference list entries when reference information is missing.

Author⁠

The author refers broadly to the person(s) or group(s) responsible for a work. An author may be

• an individual,
• multiple people,
• a group (institution, government agency, organization, etc.), or
• a combination of people and groups.

This element includes not only authors of articles, books, reports, and other works but also others who played primary roles in the creation of a work, such as editors of books, directors of films, principal investigators of grants, podcast hosts, and so on.

When you cannot determine who the author is, treat the work as having no author.

Format of individual author names

Invert all individual authors’ names, providing the surname first, followed by a comma and the author’s initials:

Author, A. A.

Use a comma to separate an author’s initials from additional author names, even when there are only two authors. Use an ampersand (&) before the final author’s name:

Author, A. A., & Author, B. B.

Provide surnames and initials for up to and including 20 authors. When there are two to 20 authors, use an ampersand before the final author’s name:

Author, A. A., Author, B. B., & Author, C. C.

When there are 21 or more authors, include the first 19 authors’ names, insert an ellipsis (but no ampersand), and then add the final author’s name.:

Author, A. A., Author, B. B., Author, C. C., Author, D. D., Author, E. E., Author, F. F., Author, G. G., Author, H. H., Author, I.           I., Author, J. J., Author, K. K., Author, L. L., Author, M. M., Author, N. N., Author, O. O., Author, P. P., Author, Q. Q., Author,                 R. R., Author, S. S., . . . Author, Z. Z.

Use one space between initials:

Author, A. A.

Write the author’s name exactly as it appears on the published work, including hyphenated surnames and two-part surnames:

Santos-García, S., & Velasco Rodríguez, M. L.

Retain the author’s preferred capitalization:

hooks, b.

van der Waal, P. N.

Format of group author names

Group authors are often government agencies, nonprofit organizations, and task forces. Follow these guidelines to format the names of group authors in the reference list.

Look at the title page or cover of the work to determine whether it has a group author or individual authors.

• If the names of individuals are presented on the title page or cover, treat the work as having individual authors.
• If only the name of the group is presented on the title page or cover, treat the work as having a group author, even if individuals are credited elsewhere in the work (e.g., in an acknowledgments section).

Spell out the full name of a group author in the reference list entry, followed by a period:

National Institute of Mental Health

On a page from an organizational or government agency website, the organization or government agency itself is considered the author, unless otherwise specified. The author of a webpage or website may also be located on an “about us” or acknowledgments page.

An abbreviation for the group author can be used in the text (e.g., NIMH for National Institute of Mental Health); however, do not include an abbreviation for a group author in a reference list entry.

Correct: National Institute of Mental Health.

Incorrect: National Institute of Mental Health (NIMH).

Incorrect: NIMH.

When numerous layers of government agencies are listed as the author of a work, use the most specific agency as the author in the reference (e.g., use “National Institute of Nursing Research” rather than “U.S. Department of Health and Human Services, National Institutes of Health, National Institute of Nursing Research”). The names of parent agencies not present in the group author name appear in the source element as the publisher.

National Institute of Nursing Research. (2015). A family’s perspective: Pediatric palliative care stories (NIH Publication No.                              15-NR-8018). U.S. Department of Health and Human Services, National Institutes of Health. https://www.ninr.nih.gov                               /sites/files/docs/NINR_508c_FamilyStories_0.pdf

Date⁠

The date refers to the date of publication of the work. The date will take one of the following forms:

• year only;
• year, month, and day (i.e., an exact date);
• year and month;
• year and season; or
• range of dates (e.g., range of years, range of exact dates).

When you cannot determine the date of publication, treat the work as having no date.

Format of the date

Follow the date format for the reference type as shown in the Publication Manual.

Enclose the date of publication in parentheses, followed by a period: (2020).

For works from a reference category that includes the month, day, and/or season along with the year, put the year first, followed by a comma, and then the month and date or season:

• (2020, August 26).
• (2018, July).
• (2019, Winter).

For unpublished, informally published, or in-progress works, provide the year the work was produced. Do not use “in progress” or “submitted for publication” in the date element of a reference.

If a work has been accepted for publication but is not yet published, use the term “in press” instead of a year.

(in press).

If a work is an advance online publication, use the year of the advance online publication in the reference.

When the date of original publication is approximate, use the abbreviation “ca.” (which stands for “circa”).

(ca. 1999).

If a date of last update is available (such as for a webpage), use it in the reference. Do not include a date of last review in a reference because content that has been reviewed has not necessarily been changed.

Retrieval dates

Include a retrieval date only if the work is unarchived and designed to change over time. Most references do not include retrieval dates.

When a retrieval date is needed, use the following format for it.

Retrieved September 30, 2020, from https://xxxxx

Title⁠

The title refers to the title of the work being cited. Titles fall into two broad categories:

• works that stand alone (e.g., whole books, reports, gray literature, dissertations and theses, informally published works, data sets, videos, films, TV series, albums, podcasts, social media, and works on websites) and
• works that are part of a greater whole (e.g., periodical articles, edited book chapters, TV and podcast episodes, and songs).

When a work stands alone (e.g., a report), the title of that work appears in the title element of the reference. When a work is part of a greater whole (e.g., a journal article or edited book chapter), the title of the article or chapter appears in the title element of the reference and the title of the greater whole (the journal or edited book) appears in the source element.

When the title of the work cannot be determined, treat the work as having no title.

Format of the title

For works that are part of a greater whole (e.g., journal articles, edited book chapters), capitalize the title using sentence case. Do not italicize the title or use quotation marks around it:

Happy fish in little ponds: Testing a reference group model of achievement and emotion.

For works that stand alone (e.g., books, reports, webpages), italicize the title, and capitalize it using sentence case:

Becoming brilliant: What science tells us about raising successful children.

For book and report references, enclose edition information, report numbers, and volume numbers in parentheses after the title. Do not add a period between the title and the parenthetical information. Do not italicize the parenthetical information. If both edition and volume information are included, separate these elements with a comma, placing the edition number first:

The psychology of music (3rd ed.).

Nursing: A concept-based approach to learning (2nd ed., Vol. 1).

If a numbered volume has its own title, the volume number and title are included as part of the main title, rather than in parentheses:

APA handbook of industrial and organizational psychology: Vol. 1. Building and developing the organization.

Finish the title element with a period. However, if the title ends with a question mark or exclamation point, that punctuation mark replaces the period:

Late-onset unexplained epilepsy: What are we missing?

Bracketed descriptions

To help identify works outside the peer-reviewed academic literature (i.e., works other than articles, books, reports, etc.), provide a description of the work in square brackets after the title and before the period. Capitalize the first letter of the description, but do not italicize the description:

Comprehensive meta-analysis (Version 3.3.070) [Computer software].

Examples of works that include bracketed descriptions are some audiobooks, gray literature (e.g., press releases), audiovisual works (e.g., films, YouTube videos, photographs), software and mobile apps, data sets, manuscripts in preparation, and dissertations and theses. Bracketed descriptions are also used in social media references to indicate attached links or images. When in doubt, include a description. Consistency of wording is helpful, but you may alter the wording shown in the examples to best convey the information readers need to understand the nature of the work.

Source

The source indicates where readers can retrieve the cited work. As with titles, sources fall into two broad categories: works that are part of a greater whole and works that stand alone.

• The source for a work that is part of a greater whole (e.g., journal article, edited book chapter) is that greater whole (i.e., the journal or edited book), plus any applicable DOI or URL.
• The source for a work that stands alone (e.g., whole book, report, dissertation, thesis, film, TV series, podcast, data set, informally published work, social media, webpage) is the publisher of the work, database or archive, social media site, or website, plus any applicable DOI or URL.
• A location is not required in the source element for most works (e.g., do not include the publisher location for book references).
• Works associated with a specific location (e.g., artwork in a museum, conference presentations) include location information in the source and, depending on the work, may also include a DOI or URL.

If a work is not recoverable, treat it as having no source.

Format of the source

The format of the source varies depending on the reference type. The most common cases are presented next.

Database information in the source

Database and archive information is seldom needed in reference list entries. For example, if you retrieved a work from an academic research database, the reference very rarely includes the name of the database or the URL of the work on the database.

Sometimes the information needed to create a reference list entry is missing or unknown. When this is the case, there are various strategies to adapt the reference.

The following table shows the basic structure of an APA Style reference to a published work, adapted for missing information, along with the corresponding in-text citations.

Anonymous authors

For a missing author, do not use “Anonymous” as the author unless the work is actually signed “Anonymous.” If the work is signed “Anonymous,” use “Anonymous” in the reference and in-text citation.

Anonymous. (2017). Stories from my time as a spy. Bond Publishers.

• Parenthetical citation: (Anonymous, 2017)
• Narrative citation: Anonymous (2017)

If the work is not actually signed “Anonymous,” the title moves to the beginning of the reference and is used in place of the author name, as shown in the table.

Presentation of the date

The date in the reference list entry for a work with a publication date may be a year only, and month and year, or a specific date (e.g., a month, day, and year); however, in the in-text citation, provide the year only.

For an in-press work, use “in press” for the date in both the reference list entry and in-text citation.

For a work with no date, use “n.d.” in both the reference list entry and the in-text citation.

Italics in the title and source

Italic formatting within the title or source varies by reference and is not shown in the table. In general, the title is italicized for a work that stands alone (e.g., book, report, webpage on a website), and some part of the source is italicized for a work that is part of a greater whole (e.g., journal article, newspaper article).