12 Mar 2024

Academic Citations and APA Style

Citations are important in academic writings, not only for acknowledging the original authors and avoiding plagiarism, but also for effective communication. Citations help readers track the evolution of thought and provide the source where they can retrieve the original material. Citations can also add strength and authority to your work. In this post, I will show how to properly cite sources in academic writings. In particular, I will follow the APA (American Psychological Association) citation style.

You may ask why bother to understand these conceps? There are a plenty of reference manager software available to help generate nicely formatted citations in various styles, e.g., Zotero (I use it too), EndNote, Mendeley, and even google scholar. However, they are only tools and do not tell us what kind of citation is needed in different situations. Moreover, it is beneficial to have a brief understanding of how the citation is formatted so that we can format simple citations by ourself (it is achievable in APA style), and even implement a function that suits our need using a programming language.

I will begin by discussing the concepts of in-text citation and the reference list, followed by demonstrations through examples. Naturally, it is impossible to cover all formatting rules in a brief post. Therefore, I will direct you to the APA style official website and illustrate how to locate resources there. Finally, I will introduce my file naming convention for references by following APA style.

In-text Citations and The Reference List

In APA style, the reference metadata are typically grouped into four elements:

author, i.e., their names;
date, in most cases., the publication year;
title, i.e., the title of the cited work;
and source, which specifies where to retrieve the cited work.

In-text citation appears within the body of the paper and contain only author and date of publication, directing readers to locate the corresponding entry in the reference list at the end of the paper, which contains additional information include title and source.

Formatting Rules for In-text Citations

There are two type of in-text citations:

parenthetical citations, where the author's surname and year appear in parentheses. This often appears at the end of a sentence, e.g.,

Falsely balanced news coverage can distort the public’s perception
of expert consensus on an issue (Koehler, 2016).

It was found that ... (Anderson & Bratos-Anderson, 1987).

It was found that ... (Reynar et al., 2010).

narrative citations, where the author's surname appears as part of the sentence, followed by the year in parentheses. In this case, & is replaced by the word and. For three or more authors, use et. al., This often appears at the beginning of a sentence, e.g.,
```
Koehler (2016) noted the dangers of falsely balanced news coverage.

Anderson and Bratos-Anderson (1987) found that ...

Reynar et al. (2010) found that ...
```

Formatting Rules for Reference List Entries

While in-text citation doesn’t vary depending on source type, reference list citations are highly variable depending on the source. As mentioned before, a reference entry includes the four elements of the author, date, title, and source; see Elements of Reference List Entries for more details.

The Author Element

Author refers broadly to the person(s) or group(s) responsible for a work. An author may be an individual, multiple people, or a group (institution, government agency, organization, etc.). When formatting, provide the surname first, followed by a comma and the author’s initials. Use a comma to separate different authors. Use & before the final author’s name. When there are too many, say 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, A. A., & Author, B. B.

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

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.

The Date Element

Date refers to the date of publication of the work. It can be year only or an exact date. When formatting, enclose the date in parentheses, followed by a period.

(2020).

(2018, July).

(2020, August 26).

The Title Element

Title refers to the title of the work being cited. When formatting, capitalize the title using sentence case and finish the title with a period¹. Italicize the title for stand alone works (e.g., books and webpages). But do not italicize for works that a part of a great whole (e.g., journal articles and conference papers).

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

The Source Element

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:

for books, the source is the publisher;
for webpages, the source is the website;
for journal articles, the source is the journal;
for conference papers, the source is the conference.

The format of the source varies depending on the reference type.

Reference type	Component of the source	Example
Journal article	Italic journal title, volume(issue), pages.	Couple and Family Psychology: Research and Practice, 8(3), 137–151.
Book	Publisher name	Springer.
Webpage on a website	Website name	Mayo Clinic.
webpage on a website (when authors are the same as the site name)	URL	https://www.cdc.gov/cancer/kinds.htm

Examples

A conference paper:

Song, Y., Sohl-Dickstein, J., Kingma, D. P., Kumar, A., Ermon, S., & Poole, B. (2021). Score-Based Generative Modeling through Stochastic Differential Equations. International Conference on Learning Representations.

A book:

Bertsekas, D., Nedic, A., & Ozdaglar, A. (2003). Convex Analysis and Optimization. Athena Scientific.

A webpage:

Dohmatob, E. (2021). Fenchel-Rockafellar duality theorem, one ring to rule’em all! - Part 1. https://dohmatob.github.io/research/2019/10/31/duality.html

For more examples, see the Reference Examples page of APA website.

The Official APA Website

The APA style official website contains a comprehensive section of Style and Grammar Guidelines, an illustrative section of Handouts and Guides, and a blog section of Posts. I recommend reading the post APA Style for beginners, in particular, the 2 minutes demonstrating video introducing the APA style website. The Academic Writer Tutorial is also highly recommended. The following cheat sheets are also useful:

A File Naming Convention for References

I always try to follow some file naming convention for electronic documents. After knowing APA style, I realize that it offers a perfect structure for naming references. In particular, I create two folders, ~/Books/ and ~/Papers/, to store my references. Each local copy is named according to a simple version of the format used in the reference list:

it does not contain the source element;
a maximum of three authors are represented;
the date element is confined to the year only;
the title element may be shortened.

Here are some examples:

Anderson, B. D. O. (1982). Reverse-time diffusion equation models.pdf

Polyanskiy, Y., & Wu, Y. (2022). Information theory.pdf

Ho, J., Jain, A., & Abbeel, P. (2020). DDPM.pdf

Goodfellow, I., Pouget-Abadie, J., ... Bengio, Y. (2014). GAN.pdf

References refs

APA Org (2020). Academic Writer Tutorial: Basics of Seventh Edition APA Style. https://extras.apa.org/apastyle/basics-7e/#/
APA Org (2024). Style and Grammar Guidelines. https://apastyle.apa.org/style-grammar-guidelines
Mendeley (2024). APA Format Citation Guide. https://www.mendeley.com/guides/apa-citation-guide/

Footnotes:

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