• Arrange the list alphabetically by the last name of authors.
  • In the reference list itself, give the names of all authors. Optionally, if the paper has more than six authors, the rest may be abbreviated to 'et al.'
  • Two or more articles by the same author (or authors) are listed chronologically.
  • For multiple works by the same first author list them chronologically.
  • Alphabetize entries with the same first author according to last names of succeeding coauthors and then by year, when the names are repeated exactly.


Shotwell, C.A., and G.W. Smith. 2001. Shotwell, O.L. 1998. Shotwell, O.L., M.L. Goulden, and C.W. Hesseltine. 1994. Shotwell, O.L., C.W. Hesseltine, and M.L. Goulden. 1993a. Shotwell, O.L., C.W. Hesseltine, and M.L. Goulden. 1997.

  • For different articles by the same author or authors published within a single year, distinguish them by adding lowercase letters to the year. Repeat identical author names in full; that is, do not use a rule to indicate names repeated from the prior entry. Do not use 'ibid.' or 'op cit.'
  • Capitalize the first letter of the first word of title and subtitles of articles, bulletins, or books, as well as capitalizing proper names as usual. Capitalize each word in conference names and journal titles, abbreviated or not.


    Doty, W.T., M. Amacher, and D.E. Baker. 1982. Manual of methods: Soil and environmental chemistry laboratory. Rep. 121. Dep. of Agronomy, Pennsylvania State Univ., University Park.

  • Journal titles are abbreviated according to an international standard, as given in Chemical Abstracts Service Source Index (CASSI, updated yearly). CASSI is available in most research libraries[Owen Science and Engineering Library]. See Appendix A for guidelines and examples. If you are unsure of the correct abbreviation, write out the title in full (or at least the part in question). The staff editors at headquarters can quickly and easily abbreviate titles, but can lose much time trying to verify the existence of incorrectly abbreviated journals and other publications. When in doubt, consult a reference librarian for the correct bibliographic citation of difficult material.

Electronic Sources

(for more on this see pg. 19 of the publications Handbook and style manual)

  • As with any reference, the idea is to make it possible for the reader to locate the exact source cited. Give all the usual information as for print publications-author, year, and title-but then provide also the entire URL address, and a date.
    • This date should be the date when the information had last been updated (e.g., from the date-posted line on a web page) or when the information was accessed (either by the author citing the work or the editor checking the reference). When in doubt, include more information rather than less.


      Online-only Publication
      Wear, D. 2000. Research projects, Southern Forest Resource Assessment Consortium [Online]. Available at http://www.rtp.srs.fs.fed.us/econ/research/sofac/projects.htm (modified 13 Mar. 2000; accessed 8 July 2000; verified 22 May 2001). USDA Forest Serv., Research Triangle Park, NC.

      Online-only Journal Article
      Kampf. S.K., M. Salazar, and S.W. Tyler. 2002. Preliminary investigations of effluent drainage from mining heap leach facilities [Online]. Available at http://www.vadozezonejournal.org. Vadose Zone J. 1:186-196.

  • Some electronic sources are the equivalent of personal communications or unpublished data (e.g., email, an online interview or chat session, or information posted on an individual home page). Cite these in the text only; include the full URL address and the date.

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