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AMA Style: Citing Your Sources: References Within Your Paper

Use AMA Style (American Medical Association Style) to format papers.

Where do I put the numbers?

Within the text in AMA Citation Style, references are numbered and the numbers are shown in superscript.

Reference numbers should appear:

  • After the fact, quotation, or idea being cited
  • Outside periods and commas
  • Inside colons and semi-colons

If citing more than one reference at the same point, separate the numbers with commas and no spaces between.


  • This drug is used to treat hepatitis. 1
  • Storing latex at high heat may cause degradation, 2,3 but it is difficult to keep materials cool in a desert environment.
  • Some physicians choose to store prescription pads in locked cabinets 4; others keep them in their coats at all times. 5

In-text citations: basics

In the document/paper/poster you are writing, materials are cited using superscript numerals. The first reference used in a written document is listed as 1 in the reference list, and a 1 is inserted into the document immediately next to the fact, concept, or quotation being cited. If the same reference is used multiple times in one document, use the same number to refer to it throughout the document.

At the end of the document, include a reference list with full citations to each item. Order citations as they appear in your paper.

You may also use author names in your writing, as long as these mentions are accompanied by numbered citations. For materials with one or two authors, include both names. For materials with 3 or more authors, include the first author's name and then et al. 


Finding treatments for breast cancer is a major goal for scientists.1,2 Some classes of drugs show more promise than others. Gradishar evaluated taxanes as a class.3 Other scientists have investigated individual drugs within this class, including Andre and Zielinski 2 and Joensuu and Gligorov. 4 Mita et al's investigation of cabazitaxel 5 seems to indicate a new role for this class of drugs.

Reference list:

1. Cancer Research Funding. National Cancer Institute. http://www.cancer.gov/cancertopics/factsheet/NCI/research-funding. Publication date unavailable. Updated June 6, 2011. Accessed November 3, 2012.

2. Andre F, Zielinski CC. Optimal strategies for the treatment of metastatic triple-negative breast cancer with currently approved agents. Ann Oncol. 2012;23(Suppl 2):vi46-vi51.

3. Gradishar WJ. Taxanes for the treatment of metastatic breast cancer. Breast Cancer (Auckl.). 2012;6:159-171.

4. Joensuu H, Gligorov J. Adjuvant treatments for triple-negative breast cancers. Ann Oncol. 2012;Suppl 6:vi40-45.

5. Mita AC, Figlin R, Mita MM. Cabazitaxel: more than a new taxane for metastatic castrate-resistant prostate cancer? Clin Cancer Res. 2012;18(24):OF1-OF6.