Note : The content of this article was written in 2010 by Laurenz Altwegg. This is just a new layout for the web.

Why are references needed

Timothy T. Allen nicely describes why and when references should be cited in scientific papers[1]:

"It is important to properly and appropriately cite references in scientific research papers in order to acknowledge your sources and give credit where credit is due. Science moves forward only by building upon the work of others. There are, however, other reasons for citing references in scientific research papers. Citations to appropriate sources show that you've done your homework and are aware of the background and context into which your work fits, and they help lend validity to your arguments. Reference citations also provide avenues for interested readers to follow up on aspects of your work — they help weave the web of science. You may wish to include citations for sources that add relevant information to your own work, or that present alternate views.

You should acknowledge a source any time (and every time) you use a fact or an idea that you obtained from that source. Thus, clearly, you need to cite sources for all direct quotations. But you also need to cite sources from which you paraphrase or summarize facts or ideas — whether you've put the fact or idea into your own words or not, you got the fact or idea from somebody else and you need to give them proper acknowledgement (even if an idea might be considered "common knowledge," but you didn't know it until you found it in a particular source).

Sources that need to be acknowledged are not limited to books and journal articles, but include internet sites, computer software, written and e-mail correspondence, even verbal conversations with other people (in person or by telephone). All different kinds of sources must be acknowledged. Furthermore, if you use figures, illustrations, or graphical material, either directly or in modified form, that you did not yourself create or design, you need to acknowledge the sources of those figures."

Which format should references and citations have?

Citations should be indicated by superscript numerals (e.g. ¹, ²) or numerals in square brackets (e.g [2], [3]) in consecutive numerical order. The references themselves should be arranged in the same order at the end of the text. In the case of numerous references, as an alternative the first three letters of the author’s last name and year in square brackets (e.g. [MIL02], [BRO99]) can be used. The references themselves should then be arranged alphabetically at the end of the text. The format of the references depends somewhat on the style adopted by the periodical or organization. The following format is good practice and is proposed by IEEE[2]. For convenience, the text by IEEE has been slightly reordered and shortened:

Articles in periodicals

Articles listed shall include the following information in the order shown:

1. Last name of author or authors and first name or initials, or name of organization
2. Title of article in quotation marks
3. Title of periodical in full and set in italics
4. Volume, number, and, if available, part
5. First and last pages of article
6. Date of issue

Example:

[1] Boggs, S. A. and Fujimoto, N., "Techniques and instrumentation for measurement of transients in gas-insulated switchgear", IEEE Transactions on Electrical Installation, vol. ET-19, no. 2, pp. 87–92, Apr. 1984.

Books

Books listed shall include the following information in the order shown:

1. Last name of author or authors and first name or initials, or name of organization
2. Title of book (in italics)
3. Edition number (if applicable)
4. Place of publication (city)
5. Name of publisher
6. Year of publication

Example:

[26] Peck, R. B., Hanson, W. E., and Thornburn, T. H., Foundation Engineering, 2nd ed. New York: McGraw-Hill, 1972, pp. 230-292.

Theses, dissertations, and other unpublished works

[5] Diessner, A., "Studies on Compressed Gas Insulation." Master’s thesis, Stanford University, 1969.

Articles presented at conferences

[3] Cookson, A. H., and Pedersen, B. O., "Thermal measurements in a 1200 kV compressed gas insulated transmission line," Seventh IEEE Power Engineering Society Transmission and Distribution Conference and Exposition, Atlanta, GA, pp. 163-167, Apr. 1979.

Standards

Standards listed shall include designation and title.

Example:

[3] ISO/IEC 7498-4, Information processing systems — Open Systems Interconnection — Basic Reference Model — Part 4: Management framework.

Articles in corporate reports

[6] Dale, S. J., "Performance of a technical and economic feasibility study of an HVDC compressed gas-insulated transmission line", Westinghouse Electric Corporation, Trafford, PA, Final Report, Dec. 1983.

Government publications

[2] Cookson, A. H., "Particle Trap for Compressed Gas Insulated Transmission Systems", U.S. Patent no. 4554399, Nov. 1985.

Web-pages

The format of web pages has not been described in Ref. [1]. Web-pages listed shall include the following information in the order shown:

1. Last name of author or authors and first name or initials, or name of organization
2. Title of article in quotation marks (in italics)
3. Year of publication, or, if and only if not available, ``retrieved'' with month and year of when page was last accessed (e.g. retrieved Nov. 07)
4. URL

Example:

[6] Timothy T. Allen, "Citing References in Scientific Research Papers", 2000, http://tim.thorpeallen.net/Courses/Reference/Citations.html

References

[1] : Timothy T. Allen, Citing References in Scientific Research Papers, 2000, http://tim.thorpeallen.net/Courses/Reference/Citations.html

[2] : IEEE Standards Style Manual, § 19 Bibliography, The Institute of Electrical and Electronics Engineers, New York, revised 2007, http://standards.ieee.org/guides/style/section7.html#992

Credits

Thanks to Laurenz Altwegg for the original version to this article.

Cover photo by Susan Q Yin on Unsplash.