Why are page numbers shown on some references and not others

Reference List: Basic Rules

Note: This page reflects the latest version of the APA Publication Manual (i.e., APA 7), which released in October 2019. The equivalent resource for the older APA 6 style can be found here.

This resource, revised according to the 7th edition APA Publication Manual, provides fundamental guidelines for constructing the reference pages of research papers. For more information, please consult the Publication Manual of the American Psychological Association, (7th ed.).

This page gives 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.

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).
• Authors' first and middle names should be written as initials.
  • 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.
• When referring to the titles of books, chapters, articles, reports, webpages, or other sources, capitalize only the first letter of the first word of the title and subtitle, the first word after a colon or a dash in the title, and proper nouns.
  • 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.
• Maintain any nonstandard punctuation and capitalization that is used by the journal in its title.
  • For example, you should use PhiloSOPHIA instead of Philosophia, or Past & Present instead of Past and Present.
• Capitalize all major words in the titles of journals. Note that this differs from the rule for titling other common sources (like books, reports, webpages, and so on) described above.
  • 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.
• Do not enclose the article title in quotes. 
  • So, for example, if you need to cite an article titled "Deep Blue: The Mysteries of the Marianas Trench" that was published in the journal Oceanographic Study: A Peer-Reviewed Publication, you would write the article title as follows:
    • Deep blue: The mysteries of the Marianas Trench.
  • ...but you would write the journal title as follows:
    • 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, 7th ed.