APSA (American Political Science Association) style is used in political science disciplines. It is the required style for APSA journals.

Parenthetical Citations

APSA format uses parenthetical citations, which are brief mentions in the text of your paper that lead the reader to the complete information about that reference. They usually appear at the end of a sentence. A parenthetical citation involves placing relevant source information in parentheses after a quote or a paraphrase. The author’s last name and the year of publication (or n.d. if there is no date) of the source from which the quotation or paraphrase is taken must appear in the text, and a complete reference should appear on your reference list.

Page or chapter numbers must be included for quotes, and should be included otherwise to point to specific data sets, ideas, or to avoid ambiguity.

For more details see the Parenthetical Citation section of the APSA Style Guide:

Examples

The growth of digital activism has added complexity to the forms of political engagement taught in Introduction to Comparative Politics courses (Vassallo 2020).

OR

The types of political engagement traditionally taught in Introduction to Comparative Politics courses "have all developed an online persona" (Vasallo 2020, 400).

Reference list entry:

Vassallo, Francesca. 2020. "Teaching Comparative Political Behavior in the Era of Digital Activitism." Journal of Political Science Education 16(3): 399-402. doi:10.1080/15512169.2019.1683454.

Reference List

Parenthetical citations will refer your reader to the full list of sources you used. This list is at the end of your paper. References are listed in alphabetical order by author’s last name.

General Format

Each reference citation is made up of the same elements that always appear in the same order. Leave out any that aren't available for or don't apply to a source. Each part of a reference is separated by a period, except when otherwise indicated. Each part begins with a capital letter unless it is a lowercase part of an author’s, editor’s, or translator’s name.

1. Name 
   • Author’s, editor’s, or translator’s names should be given as they appear with the source.The first (or only) author’s, editor’s, or translator’s name is always inverted in a reference (i.e., last name, first name). In multiauthored sources, the other authors’ names are not inverted, and are separated by commas. Use and, not an ampersand (&), before the final given name. Use the abbreviations ed. or eds., or trans. for editors or translators.
   • If the source was published by an organization, association, or corporation and does not carry an author’s name, the organization is listed as the author, even if it is also the publisher.
2. Year - The year of publication is usually the only part of the date needed in a reference. (When the year of publication cannot be located, use n.d.)
3. Title of Work - Spelling, hyphenation, and punctuation in the original title should be preserved with a few exceptions. Words in full capitals should be changed to uppercase and lowercase, headline-style capitalization should be applied throughout, and ampersands can be changed to and. Numbers should remain spelled out or given as numerals according to the original source. 

4. Volume and Numbers - For volume and page numbers, Arabic numerals should be used. The exception is if the source has any page numbers with roman numerals.

5. DOIs or URLs - Whenever a source is found, read, or used online, a direct link that leads the reader to the source should be included. It is never acceptable to only include a link to an online source, it must be included with other citation data (14.6). The preferred order for citing online sources is the following: (1) DOI (digital object identifier) numerals, (2) a permalink URL (uniform resource locator), and (3) a short version of the URL.

For more information, see the References section of the APSA Style Guide: