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Wartburg College - 100 Wartburg Blvd. - Waverly, IA 50677

Citation Guide

This guide provides a few examples of how to cite various sources in different citation styles. An explanation of citations is included on the first tab.

Vogel Library Online Guide to ACS Style



General Instructions:


1. You have 3 choices for in-text citations. Choose one and use it exclusively through the whole paper.


2. Place the citation markers at a logical point in the sentence, such as after the author’s name—not necessarily at the end of the sentence.


  1. ITALICS IN PARENTHESIS. Number citations sequentially in italics in parentheses after the quote:
  • The change in solvents had a pronounced effect on the association and dissociation of the respective molecules (1).

*Your bibliography will then be ordered numerically, ordering each new citation with the next number in sequence. If you use a source again later, use that same number again--in other words, the source above will always be (1)).

*When citing more than one source, use a dash to separate three or more contiguous sources (3-5) or a comma to separate non-contiguous sources (1,3,5).


  1. SUPERSCRIPTS. Number citations sequentially in superscript:
    • Quartz is a common mineral throughout the world, made up of silicon and oxygen12

*You make a number superscript by a command found on the Font menu in Microsoft Word.

*The same rules apply as for the first type of citation—this source will always be 12.

*Use the same rules as for above for citing more than one source: (12-14) for contiguous and (12, 16, 3) for non-contiguous.


  1. NAME-DATE. Include the Last Name, comma, and Date at the end of the sentence OR use the author’s name in the sentence and include the year immediately after in parenthesis:
    • Option 1: Drug release is controlled by varying the hydrolytic stability of the ester bond (Harris, 2003).
    • Option 2: According to Harris (2003), drug release is controlled by varying the hydrolytic stability of the ester bond.

*For more than one author, list first author only and write “et al”:

  • (Gorman et al., 2011).

*For more than one work by the same author, you have several choices, all of which distinguish between the different works. Make a choice:

  • (Knauth, 2011) and (Knauth, 2010)
  • (Knauth, 2010a) and Knauth, 2010b)
  • (Knauth, 2011) and (Knauth and Rizzo, 2011).

Your bibliography will be ordered alphabetically by author's last name.

Everything Else

Please see the style manual at the library reference desk.