APA Style Citation Guide

APA stands for American Psychological Association. The APA style for citation is popular among behavioral and social science journals. However, it is not limited to such disciplines. The style originated in 1929, created by a group of psychologists, anthropologists, and business managers to improve reading comprehension (University of Pittsburgh, 2020). The citation style has undergone many changes throughout the years.

The latest version is the APA 7th edition published in October 2019. This section draws from the APA official Style and Grammar Guidelines (American Psychological Association, n.d.).

The in-text citation along with the formatting of the reference list or bibliography section are explained in this section.

APA In-Text Citation

In-text citations let users know which ideas are attributed to whom. The APA citation style has two major elements for in-text citation: the author and the date. Also, they come in two forms: parenthetical and narrative (APA, 2019).

Parenthetical Citations

For parenthetical citations, both author and date appear separated by a comma. A parenthetical citation may appear within or at the end of a sentence.

  • …98% of participants (Smith, 2014).

Should other texts appear within the parenthetical citation, one should use commas around the year.

  • …however old the findings may be (see Bishop, 1996, for further explanation).

If both text and citation are included in parentheses, use a semicolon to separate them. Never use parentheses within parentheses.

  • …(e.g., experimental anomalies in clinical trials; Chan, 2015).

Narrative Citations

In narrative citations, the author’s last name appears in the running text while the date appears in parentheses after it. The author’s name can be placed in any part of the sentence that makes sense.

  • Yang (2004) suggested that…

In cases where both the author and date element appear in the running text, do not use parentheses.

  • In 2004, Yang concluded that…

Citations by the Number of Authors

For a single author 

  • Coleman (2019) stated that early…
  • …hominids hunted large game (Coleman, 2019).

For two authors

  • Smith and Johnson (2020) avoided the term…
  • …paradigm because of its use in ordinary language (Smith & Johnson, 2020).

For three to five authors

  • Use the last name of the first author and “et al.” even for the first citation:
    • …especially when observers are involved (James et al., 2017).

For six or more authors

  • Cite only the name of the first author, use et al., and the year:
    • …for complex adaptive systems (Chambers et al., 2019).
  • Chambers et al. (2010) put forward a model…

If the author information is not available, you can use the source title to replace the author element. When there is no date included in the source, cite the first few words of the article inside quotation marks using a headline-style capitalization with the year after the comma in your in-text citation in the form:

  • (“No Author, No Date,” n.d.).

APA Reference List Entries Format

For the reference lists located at the end of the research paper, you need to cite four major elements:

  1. Author: includes the individual author names format and group author names format
  2. Date: includes the date format and how to include retrieval dates
  3. Title: includes the title format and how to include bracketed descriptions
  4. Source: includes the source format and how to include database information

Below are the APA style rules for each of them.

APA Individual Author Names Format

When citing individual author’s names, write the surname first. This is followed by a comma then the author’s initials.

  • Kimathi, J. M.

If there is more than one author, place a comma to separate an author’s initials from subsequent author names. This is also applicable even when there are only two authors. Also, use an ampersand “&” before the final author’s name and put one space between initials.

  • Kimathi, J. M., & Yuen, C. W.

Include both surnames and initials or up to and including 20 authors. Again, in this case, use an ampersand before the last author’s name.

  • Kimathi, J. M., Yuen, C. W., & Glenn, F. V.

If there are 21 authors or more, include the first 19 authors’ names, then insert an ellipsis before adding the final author’s name. Note that you should not use an ampersand in this case.

  • Kimathi, J. M., Yuen, C.W., Glenn, F.V., James, C. T., Bahn, F. F., Childress, Y. B., Uy, J. F., Fong, U. T., Rivera, C. N., Karl, J. E., Chan, K. O., Yu, B. N., Jones, C. V., Williams, J. J., Adebayo, M. N., Tong, G. H., Prince, A. L., Santos, F. L., Garcia, J. H., . . . , Vernon, A. R.

Moreover, it is important to write the author’s name as it appears in published works. This does not only include two-part surnames and hyphenated surnames but also the author’s preferred capitalization.

  • Rodriguez-Lopez, C., & Bixler Zavala, O. M.
  • cherry, B. or de Souza, N. C.

Group Author Names Format

Usually, group authors come in the form of task forces, non-profit organizations, and government agencies. When only the name of the group is used on the cover or title page of a publication, treat it as having a group author. This is even the case when individuals are credited elsewhere in the work itself like the acknowledgment section. However, if there are individual names in the cover or title page, treat the work as having multiple individual authors.

For the reference list entry, you should spell out the full name of the group then add a period after it.

  • Correct: American Psychological Association.
  • Incorrect: APA
  • Incorrect: American Psychological Association (APA)

You can use the abbreviation of the group in the text (e.g. APA for the American Psychological Association).

Use the most specific agency as the author when there are various layers of government agencies listed. Parent agencies not appearing in the group author name should be found in the source element as the publisher of the work.

  • Minority Business Development Agency. (2015). The state of minority business enterprises: An overview of the 2007 survey of business owners. U.S. Department of Commerce. https://www.mbda.gov/page/state-minority-business-enterprises-overview-2007-survey-business-owners-0

Date Format

For most publications, you only use the year. Put the year of publication inside parentheses followed by a period.

  • (2019).

For others that require day, month, and/or season along with the year, place the month and date or season after the year. Separate them with a comma.

  • (2019, February 5).
  •  (2020, January).
  • (2014, Spring).

If the work you are citing has been accepted for publication yet is still to be published, use “in press” instead of the year. However, for in-progress works, unpublished papers, and informally published documents, never use “submitted for publication” or “in progress.” Instead, give the year the work was produced instead. Also, if you are citing a work that is an advanced online publication, use the year of the advanced online publication.

  • (in press)

For dates with an approximate date of publication use “ca.” for “circa” before the year.

  • (ca. 1968)

If you want to cite publications that are designed to change over time, you would need to provide the retrieval date for the document. Use this following format:

  • Retrieved June 11, 2020, from https://…

If there is no date available, again, use “n.d.” The entry can take the form of:

  • No Work Available. (n.d.) In Jerry’s House Help Agency. Retrieved from http://jerry…

Title Format

There are two main kinds of titles. Firstly, titles can be the name of the standalone work like books and research papers. In this case, the title of the work should appear in the title element of the reference. Secondly, they can be a part of a bigger work, such as edited chapters, podcast episodes, and even songs. In this case, the title of the article or chapter or part of the work should appear in the title element. The title of the bigger work should appear in the source element.

For standalone works, italicize the title. Also, use sentence case.

  • End of the rope: The gleeful ending of movie credits.

When citing parts of a bigger work like an edited chapter or journal articles, capitalize the title using sentence case. Do not, however, italicize the title or place it between quotation marks.

  • A critical analysis of movie credits: From fonts to scroll speeds

If there are different editions, volumes, or report numbers, include these after the title enclosed in parentheses. Do not use a period to separate the title and the parenthetical. If both volume information and edition are included, use a comma as a separator and put the edition number first.

  • Necromancy and witchcraft (6th ed.).
  • Casting spells: For little boys and girls (3rd ed., Vol. 6).

When the numbered volume has its own title, both of them should be included as part of the main title instead of the parenthetical information. Also, the title element should be finished with a period whenever the title does not end with a question mark or exclamation point. In cases where titles do, use the appropriate punctuation marks.

  • Birdwatching handbook for the visually-impaired enthusiast:  Vol. 2. Seeing through sounds.
  • Why birds sing their songs?

When citing works outside the peer-reviewed academic literature, give a description of the work in square brackets after the title but before the period. You should capitalize the first letter but do not italicize the description. Do this for YouTube videos, audiobooks, manuscripts in preparation, theses, and others. Moreover, bracketed descriptions can also be used for social media references.

  • Economic stimulation simulation (Version 1.0.5) [Computer software].
  • Curling updates. (2020, January 15). Get to know the rising stars in Canada. Will one of them be the Michael Jordan of curling? [Image attached] [Status update]. Facebook. https://www.facebook.com/xxx.xxx.x.xxxx…

Source Format

Different sources require different formatting conventions. There are usually six types of source references commonly cited: journal articles, conference papers, authored book or whole edited book, edited book chapter, webpage on a website with authors different from the site name, and webpage on a website where authors name is the same with the site.

For journal articles, there are five components: periodical title, volume, issue, page range, and DOI or URL. So, for the article with the title “The Basic Problem of the Theory of Levels of Reality” by Roberto Poli published in 2001, you write the reference as:

Above, “Axiomathes” is the name of the journal, “12” is the volume number, “3” is the issue number, and “261-283” is the page range.

When citing a paper or session in a conference that is not formally published in the proceedings, the format is:

  • Author, F. M. (Year, Month). Title of contribution. [Type of contribution]. Conference Name, City. DOI or URL when applicable.
    • Example: Johns, Y. (2018, January). An analysis of Klingon syntax. [Poster presentation], Fictional Language Conference 2018, Auckland, New Zealand. https://bit.ly/xxxxx

When citing an authored book or whole edited book, provide the name of the publisher and the DOI or URL. The format is:

  • Author, F. N. (Year). Title of book. Publisher. DOI or URL if available.
    • George, R. F. (2009). Quicks and other tells. Rubbarb. https://doi.org/xx.xxx/x.xxxxxx

And, when citing a book chapter for edited books, you cite each chapter separately. When citing more than one chapter, you cite each chapter as a different source. The format is:

  • Author, F. N. (Year). Chapter title. In Editor(s) name(s) (Ed.), Book title (page range). Publisher. DOI or URL if applicable.
    • Example: Spurlock, C. (2005). Dire consequences of plagiarism. In J. Morgan & C. Spurlock (Eds.), The greatest blunders in publishing (pp. 65-72). Hop Press.   https://doi.org/xx.xxx/xxxx

For webpages that have different authors’ names from the site name, provide the website name and the URL for the source element. For webpages whose authors’ names are the same as the site, only provide the URL.

  • Bikram News. https://www.bikramnews.com/xxx-xxx/xxx
  • https://www.sinkholeobserver.com/xx/x

Database Information

In APA style references, DOIs and URLs are used. DOI is short for digital object identifiers. These are alphanumeric strings identifying unique content while providing a persistent link to their locations. You can find these in database records and reference lists.

DOIs come in the form of: “https://doi.org/xxxxx” where “xxxxx” is the DOI number. On the other hand, URL is short for uniform resource locators. These are basically the links you find on the address bar of your browser. So, when do you include DOIs and URLs? Here are the APA guidelines.

  • When a work has a DOI, include a DOI regardless of whether you used the online or print version.
  • If you are using a print work without a DOI, do not include a URL or DOI.
  • When citing an online work that has both DOI and a URL, only include the DOI.
  • If an online work has no DOI but has a URL, include the URL in the reference when citing websites without DOIs, not including academic research databases. Make sure the URL works for your readers.
  • When citing works in academic research databases without DOIs, do not include a URL or database information. The reference should be the same as the ones in print versions. This is because the work is already widely available.
  • If citing works from databases publishing exclusive original propriety material (e.g. UpToDate database), or for works of limited circulation (e.g. monographs in the ERIC database), provide the name of the database and the URL of the work. In cases where the URL needs a login to access, give the URL of the home page or the log-in page instead of the direct URL of the work.

In the APA style, you do not include other alphanumeric identifiers, such as the International Standard Serial Number (ISSN) and the International Standard Book Number (ISBN). Also, when using DOIs and URLs, present them as hyperlinks. This means they begin with “http:” or “https:”.  And, it is acceptable to display the link in blue font and underlined like in the default setting in your word-processing software or you can use plain text.

Examples of APA Reference List

In this section, an example of a reference list containing different types of sources that you could use as a quick guide.


  • Ridley, M. (1994). The red queen: Sex and the evolution of human nature. Penguin UK.

Chapter of an Edited Book

  • Spurlock, C. (2005). Dire consequences of plagiarism. In J. Morgan & C. Spurlock (Eds.), The greatest blunders in publishing (pp. 65-72). Hop Press.   https://doi.org/xx.xxx/xxxx

Journal Article

  • Benoit, J. N., Barrowman, J. A., Harper, S. L., Kvietys, P. R., & Granger, D. (1984). Role of humoral factors in the intestinal hyperemia associated with chronic portal hypertension. American Journal of Physiology-Gastrointestinal and Liver Physiology247(5), G486-G493.

Conference Paper/Presentation

  • Dodson, J. (2005, April). Faith and medicine [Conference session]. Medical Sociology 2005, Austin, Texas.



  • Dough, K. (2009). The future rationale of post-modernist art [Unpublished doctoral dissertation]. Academy of Art University. San Francisco, California.