purdue owl apa online

Purdue Online Writing Lab Purdue OWL® College of Liberal Arts

Reference List: Basic Rules

Welcome to the Purdue OWL

This page is brought to you by the OWL at Purdue University. When printing this page, you must include the entire legal notice.

Copyright ©1995-2018 by The Writing Lab & The OWL at Purdue and Purdue University. All rights reserved. This material may not be published, reproduced, broadcast, rewritten, or redistributed without permission. Use of this site constitutes acceptance of our terms and conditions of fair use.

This resourse, revised according to the 7 th  edition APA Publication Manual, offers basic guidelines for formatting the reference list at the end of a standard APA research paper. Most sources follow fairly straightforward rules. However, because sources obtained from academic journals  carry special weight in research writing, these sources are subject to special rules . Thus, this page presents basic guidelines for citing academic journals separate from its "ordinary" basic guidelines. This distinction is made clear below.

Note:  Because the information on this page pertains to virtually all citations, we've highlighted one important difference between APA 6 and APA 7 with an underlined note written in red.  For more information, please consult the   Publication Manual of the American Psychological Association , (7 th  ed.).

Formatting a Reference List

Your reference list should appear at the end of your paper. It provides the information necessary for a reader to locate and retrieve any source you cite in the body of the paper. Each source you cite in the paper must appear in your reference list; likewise, each entry in the reference list must be cited in your text.

Your references should begin on a new page separate from the text of the essay; label this page "References" in bold, centered at the top of the page (do NOT underline or use quotation marks for the title). All text should be double-spaced just like the rest of your essay.

Basic Rules for Most Sources

• All lines after the first line of each entry in your reference list should be indented one-half inch from the left margin. This is called hanging indentation.
• All authors' names should be inverted (i.e., last names should be provided first).
• For example, the reference entry for a source written by Jane Marie Smith would begin with "Smith, J. M."
• If a middle name isn't available, just initialize the author's first name: "Smith, J."
• Give the last name and first/middle initials for all authors of a particular work up to and including 20 authors ( this is a new rule, as APA 6 only required the first six authors ). Separate each author’s initials from the next author in the list with a comma. Use an ampersand (&) before the last author’s name. If there are 21 or more authors, use an ellipsis (but no ampersand) after the 19th author, and then add the final author’s name.
• Reference list entries should be alphabetized by the last name of the first author of each work.
• For multiple articles by the same author, or authors listed in the same order, list the entries in chronological order, from earliest to most recent.
• Note again that the titles of academic journals are subject to special rules. See section below.
• Italicize titles of longer works (e.g., books, edited collections, names of newspapers, and so on).
• Do not italicize, underline, or put quotes around the titles of shorter works such as chapters in books or essays in edited collections.

Basic Rules for Articles in Academic Journals

• Present journal titles in full.
• Italicize journal titles.
• For example, you should use  PhiloSOPHIA  instead of  Philosophia,  or  Past & Present   instead of  Past and Present.
• This distinction is based on the type of source being cited. Academic journal titles have all major words capitalized, while other sources' titles do not.
• Capitalize   the first word of the titles and subtitles of   journal articles , as well as the   first word after a colon or a dash in the title, and   any proper nouns .
• Do not italicize or underline the article title.
• Deep blue: The mysteries of the Marianas Trench.
• Oceanographic Study: A Peer-Reviewed Publication

Please note:  While the APA manual provides examples of how to cite common types of sources, it does not cover all conceivable sources. If you must cite a source that APA does not address, the APA suggests finding an example that is similar to your source and using that format. For more information, see page 282 of the   Publication Manual of the American Psychological Association , 7 th  ed.