References are found at the end of a manuscript and are titled “References,” and each item should be listed in numerical order (two references should not be combined under a single reference number) as opposed to alphabetically. Additionally, each item should be single-spaced.

Sample Reference

AuthorLastname FirstInitialMiddleInitial. Title in sentence case. Abbreviated Journal Title in Title Case. Year;volume(Issue#):PP-PP. doi: ##

If you are citing an online article, you should include the day and month of publication as well in the format of Month Day, Year.

Use sentence case for all titles (capitalize only the first word of the title). Abbreviate and italicize names of journals according to the listing in the National Library of Medicine database.

Author Names

When writing up your references list, be sure to always include the last name and the first and middle initial of the authors without punctuation. However, do use a comma to separate more than one author in a single bibliographic group (e.g., Wheeler T, Watkins PJ).

If the author's middle initial isn't available, omit it. The abbreviations "Jr" and "Sr" ("Junior" and "Senior") may follow authors' names when applicable (e.g., Jameson JJ Jr). Use Roman numerals to signify "2nd," "3rd," "4th," and so on (e.g., Doe JF III).

Use all authors’ names unless there are more than 6 authors. In that case, list the names of the initial 3 authors, followed by “et al” in place of the others.

Bibliographic Elements

Each reference is divided with periods into bibliographic groups; each bibliographic group contains bibliographic elements, which may be separated using the following punctuation marks:

• A comma: if the items are sub-elements of a bibliographic element or a set of closely related elements (e.g., the authors’ names).

• A semicolon: if the elements in the bibliographic group are different (e.g., between the publisher’s name and the copyright year) or if there are multiple occurrences of logically related elements within a group; also, before volume identification data.

• A colon: before the publisher’s name, between the title and the subtitle, and after a connective phrase (e.g., “In,” “Presented at”).

See the following examples:

In-Text Citations

Each reference should be cited in the text using superscript arabic numerals. These superscript numbers should be outside periods and commas but inside colons and semicolons. Multiple references may be cited in the same instance. If you are citing sequential references, these should be indicated with a hyphen. Nonsequential references should be separated with commas. There should not be a space between numbers. For example: 

As Smith et al have reported,^1-3,5

Smith et al reported^1-3,5:

AMA recommends that you do not place a superscript reference citation immediately following a number, and advises that you revise the sentence to prevent any possible confusion with an exponent.

Parenthetical citations should ONLY be used for items that do not occur in the references list, such as unpublished material, personal communications, and news articles. These citations may or may not include a title or author, but should include page numbers and, if possible, a DOI or URL.