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AMA Style (11th ed): Citing Your Sources

11th edition (2020) AMA style

is this an online book or web site?

Just because you are viewing the item online, doesn't mean it's a web site.

Online or electronic books are published once and are revised on a set schedule. Online books usually have a print equivalent that contains the exact same information. Electronic books usually require payment to access. USC Libraries license many electronic books for use by USC affiliates.

Electronic journals are also published on a set schedule (usually monthly or quarterly). These also have print equivalents and require payment to access. USC Libraries license many electronic journals for use by USC affiliates.

Web sites are published once, then updated as information is developed or discovered. Web sites do not have a print equivalent. USC Libraries do license some web sites for use by affiliates, but the majority of web sites are free to all.

Online Materials

AMA style requires you to cite the version of an item you have read (e.g., an article might be available online and in a print journal. If you read the online copy, cite the online copy). Print and online citations are very similar in format.

For citing e-articles, include a DOI (Digital Object Identifier).

For citing e-books, include the date you accessed the book, and a DOI. If DOI is not available, use the URL.

For citing websites, include the publication date, updated date, accessed date, and URL. Note that the publication date is just written as a date, omitting the word "Published"; only the updated and accessed dates include these words alongside the date. If publication or update dates are not available, omit these sections.

Journal article viewed in electronic form with DOI available:

Towfighi A, Markovic D, Ovbiagele B. Utility of Framingham coronary disease risk score for predicting cardiac risk after stroke. Stroke.2012;43(11):2942-2947. doi: 10.1161/STROKEAHA.112.668319

Journal article viewed in electronic form, but the journal does not use DOI:

Ng L, Karunasinghe N, Benjamin CS, Ferguson LR. Beyond PSA: are new prostate cancer biomarkers of potential value to New Zealand doctors? N Z Med J. 2012;125(1353). Accessed April 15, 2020. https://www.nzma.org.nz/journal-articles/beyond-psa-are-new-prostate-cancer-biomarkers-of-potential-value-to-new-zealand-doctors/

Book viewed in electronic form:

Suchmacher M, Geller M. Practical Biostatistics. Elsevier; 2012. Accessed November 5, 2012. http://www.sciencedirect.com/science/book/9780124157941

Edited book viewed in electronic form:

Brunton LL, Blumenthal DK, Murri N, Hilal-Danden R, Knollmann BC, eds. Goodman and Gilman’s the pharmacological basis of therapeutics. 12th ed. McGraw-Hill; 2011. Accessed November 4, 2012. http://www.accesspharmacy.com.libproxy.usc.edu/resourceToc.aspx?resourceID=28

Chapter within an edited book viewed in electronic form:

Relling MV, Giacomini KM. Chapter 7. Pharmacogenomics. In: Brunton LL, Blumenthal DK, Murri N, Hilal-Danden R, Knollmann BC, eds. Goodman and Gilman’s the pharmacological basis of therapeutics. 12th ed. McGraw-Hill; 2011. Accessed October 4, 2012. http://www.accesspharmacy.com/content.aspx?aID=16659580

Web site:

Warfarin. Drug Information Online: Drugs.com. September 1, 2012. Updated January 23, 2020. Accessed April 15, 2020. http://www.drugs.com/cons/warfarin.html

Tips for Citations

Capitalization of titles in references:

Book titles: capitalize all major words. Do not capitalize the, an, a, in, for, or but, unless this word begins the title. Acronyms (NIH, HIV, etc.) should be shown in all caps. 

Chapter titles within books: capitalize only the first word. Acronyms (NIH, HIV, etc.) should be shown in all caps.

Journal titles: capitalize all major words. Do not capitalize the, an, a, in, for, or but, unless this word begins the title. Acronyms (NIH, HIV, etc.) should be shown in all caps. 

Journal article titles: capitalize only the first word. Acronyms (NIH, HIV, etc.) should be shown in all caps. 

Personal communications:

AMA Style states that personal communications such as phone calls, emails, conversations, etc. are not included in the reference list. However, you should cite these materials parenthentically within the text. Provide the name and highest academic degree of the author, type of communication, and date sent. If this would compromise patient anonymity, replace the name with a title and remove the day of communication.

Examples:

Individuals on this new experimental drug should not take aspirin. (Sara P. Norris, M.D., email communication, November 3, 2012.)

For all five patients I have seen with this rare disorder, I have prescribed Interferon. (Physician at LAC + USC Healthcare Network, phone call, October 2012).

Anonymous works:

Follow the citation style for book, journal, web site, etc., and omit the author name. 

Non-scholarly materials appearing in journals (editorials, letters to the editor, comments, interviews, etc.):

Cite these using the article style.

How to cite information when there is no guidance on this website:

Read the AMA Manual of Style, section 3, to find guidance for citing many other types of publications and information.

If there is no guidance on your specific type of information, adapt an existing AMA citation style.