• 4-minute read
• 17th February 2020

How to Format an NLM Reference List

NLM referencing is used by many medical schools and journals. Thus, if you are studying medicine, you may need to use NLM referencing in your written work. And in this post, to help out, we’ll look at the basics of how to format an NLM reference list. Read on to find out more.

NLM Reference List Rules

In NLM referencing, as well as citing sources in the main text, you need to list each cited source at the end of your document. This list can be titled ‘References’, ‘End References’, ‘Literature Cited’, or ‘Bibliography’ (check your university’s style guide if you are not sure which to use). Beyond this, there are some rules that apply to reference lists in NLM referencing:

• Write author and editor names surname first.
• Use initials in place of first and middle names.
• List all named authors for each source, regardless of how many there are.
• Use a comma to separate author names in each entry.
• Capitalise only the first word of book and article titles, along with proper nouns, proper adjectives, acronyms, and initialisms in titles and subtitles.
• Reproduce other titles (e.g. web pages) as they were originally published.
• Abbreviate significant words in journal titles (and omit other terms).
• Use a colon followed by a space to separate titles from subtitles.
• For online sources, include a citation date in square brackets after the date of publication; you should also give a URL at the end of the reference after the words ‘Available from’.

Otherwise, how you organise a reference list will depend on the citation style used in the document. In the rest of this post, then, we will look at how to format an NLM reference list when using the citation-sequence, citation-name, and name-year versions of this system.

NLM Reference List: Citation-Sequence

In the citation–sequence system, you cite sources with superscript numbers in the main text. These numbers point to entries in the reference list, with sources listed in the order they are first cited. As such, the first source you cite becomes the first entry in your reference list, the second source you cite would become the second entry, etc. For instance:

1. Hopper D, Farrow A. Medical bibliographies. J Med Writ. 2008 June 15; 4(1): 128-130.

2. Aaronson A. A history of English alphabetization. New York, NY: Penguin; 1998. 480 p.

3. Zedwick Z. Understanding NLM [Internet]. Bethesda, MD: National Library of Medicine; 2011 Jan 5 [cited 2018 Nov 11]. Available from: http://www.nlm.nih.gov/NLM-referencing.

Here, for example, the fact that ‘Medical bibliographies’ by Hopper and Farrow is the first source in the list would mean that it is also the first source cited in the document. We would then know that any citation with a superscript ‘1’ in the text points to this entry in the reference list.

NLM Reference List: Citation-Name

The citation-name system is similar to the citation-sequence version in that you cite sources with numbers in the main text, with each number indicating a source in the reference list.

However, with this version of NLM referencing, you order sources in the reference list itself alphabetically by author surname. With this version of the system, then, our NLM reference list would look like this:

1. Aaronson A. A history of English alphabetization. New York, NY: Penguin; 1998. 480 p.

2. Hopper D, Farrow A. Medical bibliographies. J Med Writ. 2008 June 15; 4(1): 128-130.

3. Zedwick Z. Understanding NLM [Internet]. Bethesda, MD: National Library of Medicine; 2011 Jan 5 [cited 2018 Nov 11]. Available from: http://www.nlm.nih.gov/NLM-referencing.

‘Aaronson’ is first above because ‘A’ comes before ‘H’ and ‘Z’ in the alphabet. We would then cite each source with its entry number in the reference list.

NLM Reference List: Name-Year

Things are a little different in the name-year citation system. In this version of NLM referencing, you cite sources by giving the author’s surname and a year of publication in brackets. In the references at the end of the document, meanwhile, you list all sources alphabetically by author surname:

Aaronson A. 1998. A history of English alphabetization. New York, NY: Penguin. 480 p.

Hopper D, Farrow A. 2008. Medical bibliographies. J Med Writ. 4(1): 128-130.

Zedwick Z. 2011. Understanding NLM [Internet]. Bethesda, MD: National Library of Medicine; [cited 2018 Nov 11]. Available from: http://www.nlm.nih.gov/NLM-referencing.

The list here is, then, in the same order as with the citation-name system. However, there are two major differences:

• We do not number sources as there are no numbered citations.
• Because we use the year of publication for sources in citations, we give this detail immediately after the author’s name in the reference list.

Otherwise, though, this version of NLM referencing is the same as the other versions above. And if you’d like your referencing checked by the experts, why not submit a document for proofreading?