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References Page Citation Guide

APA Citation has been broken down into three sections: Print Sources, Online Sources, and Online Periodicals. For further examples and instruction, ask a teacher or librarian, stop by the Academic Resource Center, or visit the Purdue Online Writing Lab. OWL's offers several pages of helpful resources that range from Basic Rules to more specific citation examples.

Reference List

  1. Citations in the References are alphabetized by (first) author’s last name, or title if no author, and are aligned to the left margin in the first line with all subsequent lines having a hanging tab.
  2. The order of authors in scientific research articles is relevant, and that order should not be altered. The first author named is the primary author, and his or her last name will determines the article’s place in your alphabetized References list.
  3. References include only the initials of the first and middle names of all authors.
  4. The Reference list does, however, include the full last names and initials of the first seven authors of source. If there are more than seven authors, then list only the first six, followed by an ellipses, and then list the last author’s name.
  5. If there are multiple titles written by the same author, then those titles are listed chronologically (oldest to newest) in the References list.
  6. Italicize titles of longer works such as books and journals. Do not italicize, underline, or put quotes around the titles of shorter works such as journal articles or essays in edited collections.
  7. Pay attention to title capitalization and punctuation in the examples below.

Examples of Citations for Print Sources

Basic Book Format:

Author. Last, first initial. (Date). Title (italicized). City of publication, State/Country: Publisher.

(In the case of multiple authors, all are noted – separated by commas, with “&” sign before final author’s last name.)


Davis, R. E. (2006). Modern chemistry. Orlando: Holt, Rinehart and Winston.

Scholarly Journal (paginated by issue):

Baelish, P.  (1973). King’s Landing:  A geopolitical analysis of Machiavellian machinations in Westeros. Seven Kingdoms

Studies in Diplomacy, 15(1), 41–50.

Daily Newspaper:

 West, K. (2009, September 13). I’ma let you finish. Los Angeles Times, p. A1.

Examples of Citations for Online Sources

In APA citation, online sources often include what are known as DOIs, or digital object identifiers. If a DOI is available, it is used in place of a URL.  The DOI is a serial number that identifies the source regardless of URL changes, and is often found on the first page of an online source.                                   

Whole Website:

Library of Congress. (2015). Woody Guthrie and the Archive of American Folk Song: Correspondence, 1940-1950. Retrieved from US LOC  website


Lopes, P. (2009). Demanding respect : The evolution of the American comic book. Philadelphia, PA, USA: Temple University Press. Retrieved from

Examples of Citations for Online Periodicals

In APA periodical citation, authors are named by their last name followed by initials; the publication year goes between parentheses and is followed by a period. Only the first word and proper nouns are capitalized for article titles. Periodical titles are written in title case and followed by the volume number, which, with the title, is also italicized.

Scholarly Journal Article from a Library Database:


With URL:

Siegel, F. (1992). Clown Politics: report on the International Clown-Theatre Congress. TDR (1988-), 36(2), 182-186. Retrieved May 29, 2015,


            With DOI:

Rees, C. E., & Monrouxe, L. V. (2010). “I should be lucky ha ha ha ha”: The construction of power, identity and gender through laughter within

medical workplace learning encounters. Journal of Pragmatics, 42(12), 3384-3399. doi:10.1016/j.pragma.2010.05.004

Online Magazine/Newspaper Article: 

With URL:       

Piggy, M. (2004). Of frogs and men. Nature. Retrieved from

With DOI:

Stokstad, E. (2004). Loss of dung beetles puts ecosystems in deep doo-doo. Science, 305(5688), 1230.