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A Guide to Footnotes and Endnotes for NASA History Authors

This document briefly explains how and when historians should use citations in their writing. It focuses on when an author needs to provide background information in a footnote or endnote. For guidance on stylistic matters such as use of italics and underlining, it points authors to other guides.

Reasons for Footnotes

History is written by a process of argument. A good argument puts forward a point of view that is well grounded: it has evidence to support it. Unlike practitioners of other fields such as engineering or the natural sciences, historians pose questions that rarely have definitive answers or solutions. The emphasis in history is on an analysis of past events using a variety of historical evidence. Because much of the historian's task is interpretative, there are strict requirements regarding the correct citation of sources. Scholars use footnotes and/or endnotes for a variety of reasons including:

  • To make it clear to the reader which views are yours and which are the views of other writers;
  • To allow you to acknowledge your intellectual debts to others if you decide to accept their views or information;
  • To direct the reader by the most efficient signposts to the place where the information you have provided can be checked and verified or where further useful information is.

Correspondingly, there are a number of situations where you MUST cite your sources.

  • Direct quotations
  • Any material that has been paraphrased from an outside source
  • Any reference to arguments or facts (i.e. budget figures, technical specifications) that have been garnered from an outside source

There are also circumstances in which you SHOULD footnote

  • To provide the reader with a guide to the sources used in the formation of the author's original argument
  • To provide the reader with a guide to sources that offer further information on ideas or arguments summarized in the author's text
  • To offer the reader further details or discussion beyond what could be reasonably included in the main text.
  • If information is not common knowledge to the average lay reader.

Number of Notes

  • If there is more than one sentence in a single paragraph that requires a footnote you may consolidate these by putting multiple sources in a single note and the end of the paragraph. If you choose to do this, you MUST arrange the sources in the footnote to correspond to the appropriate sentences in your text. You must also explain any potential ambiguities about which source refers to what information within the paragraph.
  • You should NEVER use one footnote to refer to material in more than a single paragraph of text .
  • So for each paragraph, you should ask yourself the following question: What primary and/or secondary sources did I use in the creation of this paragraph?

Web citations

  • While it is acceptable to cite electronic sources (emails, Web sites, online journals, online databases, etc.), if it is at all possible we would prefer to have the reference to the original material that was used in the creation of the electronic document.
  • When referencing a Web site, it is imperative that the author include the date that the site was accessed online in the citation. In addition, the author needs to print out the electronic document for inclusion in the appropriate Historical Reference Collection. These precautionary steps ensure that if an ephemeral Web site disappears later, there will still be a record of the content material.
  • Please do NOT cite on-line encyclopedias such as Wikipedia for several reasons. First, Wikiipedia does not list the author or creator of the information. Second, its content changes frequently. Third, encyclopedias usually contain factual information. (If you don't know certain facts, it's obviously fine to look them anywhere you choose, but facts typically do NOT need to be footnoted).

Additional Information

  • As a stylistic matter, you may use either footnotes or endnotes, but we usually prefer footnotes.
  • Primary Sources from the NASA Center and Headquarters history reference collection should specifically include the file folder name and number and be cited in the following format:
    • Author's Name, Title of Document, Folder/File Name, Folder/File Number, NASA Center (Headquarters, Dryden, etc.) Historical Reference Collection, Location (Washington, DC, etc.)
  • By using citations properly, authors avoid the serious offense of plagiarism. There is an excellent guide to avoiding plagiarism that was prepared at Virginia Polytechnic Institute and State University ("Virginia Tech") as part of its graduate student honor code. This guide includes some examples of plagiarism that may surprise some writers. The guide is very accessible and relevant to scholarly historical work, such as that which the NASA History Division produces so we highly recommend this.
  • More information about historical argumentation is at on the Web.
  • All these steps are designed so that if anyone, including the author, has any doubts or questions about the origin of a particular piece of source material, he or she could simply look it up!

Stylistic Matters

Bonni Cermak and Jennifer Troxell, Authors
Steve Garber, NASA History Web Curator

For further information email

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