Skip to Main Content
It looks like you're using Internet Explorer 11 or older. This website works best with modern browsers such as the latest versions of Chrome, Firefox, Safari, and Edge. If you continue with this browser, you may see unexpected results.
Skip to main content

Citing Sources

This guide will assist you with citing sources in your papers.

Why You Need Style Guide Information

This guide contains several tools that will cite sources in your paper. However, they are not perfect and some basic knowledge of citations styles is required.

NLM/Vancouver Style Guide

Internal Citations

Internal or in-text citations are used reference source material within the body of an article, research paper, etc.  A reference list or bibliography is the full list of citations that is usually located at the end of a paper.

Citing Medicine does not specify which style to use for formatting internal citations, but we recommend using numerical superscripts. Citations at the end of the paper should be presented in the order they were cited.  


Shrodinger’s cat posits that a cat in a box can be both living and dead at the same time until the moment the box is opened.  Some have suggested that the cat can also be in two different boxes at the same time.1


1. Feltman R. Schrödinger’s cat just got even weirder (and even more confusing). [cited 2018 August 13]. Available from Accessed through The Washington Post Speaking of Science Blog.

Examples of NLM/Vancouver Style Citations

How to Cite Biomedical Information

Many people use the Vancouver style (aka Recommendations for the Conduct, Reporting, Editing and Publication of Scholarly Work in Medical Journals (ICMJE Recommendations)) to cite biomedical information. This style was developed by the International Committee of Medical Journal Editors.

The rules to use for citing references can be found in the free ebook Citing Medicine which is put out by the National Library of Medicine.

Electronic Material:

Electronic Journal Article with page numbers

Polgreen PM, Diekema DJ, Vandeberg J, Wiblin RT, Chen YY, David S, Rasmus D, Gerdts N, Ross A, Katz L, Herwaldt LA. Risk factors for groin wound infection after femoral artery catheterization: a case-control study. Infect Control Hosp Epidemiol [Internet]. 2006 Jan [cited 2007 Jan 5];27(1):34-7. Available from:

Electronic Journal Articles without page numbers

Diederichs G, Engelken F, Marshall M, Peters K, Black DM, Issever AS, Barrett-Connor E, Orwoll E, Hamm B, Link TM, Osteoporotic Fractures in Men Research Group. Diffuse idiopathic skeletal hyperostosis (DISH): Relation to vertebral factures and bone density. Osteoporos Int. [Internet]. 2010 Sep 4 [cited 2011 Jan 25]; [9 p.]. Available from

UpToDate is cited like an electronic book where the entry is treated as a chapter.

Marion DW. Diaphragmatic pacing. In: Basow, DS editor. UpToDate. Waltham, MA: UpToDate; 2011 [cited 2011 Jan 13].

When referencing a Micromedex® product or database, you first need to figure out if you are citing the whole Micromedex resource, or a specific part of Micromedex. You should be able to tell by looking at the top of the entry.

As a whole:

Micromedex® 2.0 [Internet]. Truven Health Analytics, Greenwood Village, Colorado, USA. [updated 2015; cited 2015 Mar 09]; Available from Registration and login required.

For an individual section or document, see "Citing Micromedex;" it's located in the "Support and Training" section near the bottom center of the home page.

Electronic book

Lawrence RA. A review of the medical benefits and contraindications to breastfeeding in the United States. Arlington (VA): National Center for Education in Maternal and Child Health; 1997 Oct [cited 2000 Apr 24]. Available from:

Electronic Book, no author

1998 state of Maryland crime control and prevention strategy. Baltimore (MD): Governor’s Office of Crime Control & Prevention; 1999 [cited 2000 Dec 19].

Electronic dictionary entry

Merriam-Webster medical dictionary [Internet]. Springfield (MA): Merriam-Webster Incorporated; c2005 [cited 2006 Nov 16]. Available from:

Electronic book chapter

Monath TP. Dengue: the risk to developed and developing countries. In: Roizman, Bernard, editor. Infectious diseases in an age of change: the impact of human ecology and behavior on disease transmission. Washington: National Academy Press; 1995 [cited 2000 Apr 4]. Available from:

Web Page

National Institute of Aging. Alzheimer's Disease Fact Sheet. [cited 2008 May 23]. Available from: Accessed through MedlinePlus.

Articles in Journals:

Standard Journal Article

List all of the first six authors; six or more, include first six followed by et al.

Vega KJ, Pina I, Krevsky B. Heart transplantation is associated with an increased risk for pancreatobiliary disease. Ann Intern Med 1996 Jun 1; 124 (11):980-3.

Organization as author

The Cardiac Society of Australia and New Zealand. Clinical exercise stress testing. Safety and performance guidelines. Med J Aust 1996; 164:282-4.

No author given

Cancer in South Africa [editorial]. S Afr Med J 1994; 84:15.

Books and Other Monographs:

Personal author(s)

Ringsven MK, Bond D. Gerontology and leadership skills for nurses. 2nd ed. Albany (NY): Delmar Publishers; 1996.

Editor(s), compiler(s) as author

Norman IJ, Redfern SJ, editors. Mental health care for elderly people. New York: Churchill Livingstone; 1996.

Organization as author and publisher

Institute of Medicine (US). Looking at the future of the Medicaid program. Washington: The Institute; 1992.

Chapter in a book

Phillips SJ, Whisnant JP. Hypertension and stroke. In: Laragh JH, Brenner BM, editors. Hypertension: pathophysiology, diagnosis, and management. 2nd ed. New York: Raven Press; 1195. p.465-78.

Conference paper

Bengtsson S, Solheim BG. Enforcement of data protection, privacy and security in medical informatics. In: Lun KC, Degoulet P, Piemme TE, Rienhoff O, editors. MEDINFO 92. Proceedings of the 7th World Congress on Medical Informatics; 1992 Sep 6-10; Geneva, Switzerland. Amsterdam: North-Holland; 1992. p.1561-5.