Skip to Main Content

Chemistry & Biochemistry

Chemistry & Biochemistry Resource Guide for Cal Poly Pomona Students and Faculty

ACS Citation Style

If you're a chemistry student or working on a paper for Chemistry or Biochemistry, you'll likely need to utilize the American Chemical Society's (ACS) Citation Style! Here are some general guidelines for working in ACS, more resources and examples can be located through the links at the bottom of this page!

In text-citations

ACS cites in-text in one of two ways:

  1. By superscript numbers, which appear outside the punctuation, if the citation applies to the whole sentence or clause.
    Example: Oscillation in the reaction of benzaldehyde with oxygen was reported previously.⁴ 
  2. By italic numbers in parentheses on the line of text and inside the punctuation.
    Example: The mineralization of TCE by a pure culture of a methane-oxidizing organism has been reported (6).

Remember:

  • Use only one method of in-text citation and be consistent.
  • Cite the reference in a logical place.
  • With numerical reference citations, start with 1 and number consecutively throughout the paper, including references in text and those in tables or figures. If a reference is repeated, DO NOT give it a new number, use the original.
  • When citing more than one reference at one place citing with one of the numeric systems, list the numbers in ascending order and separate them by commas (no spaces in superscript, spaces in line). If they are part of the consecutive series, use a dash to indicate a range of 3 or more. 

                     Example:  ...in the literature⁴˒⁵˒⁷⁻⁹ 

                                      ...in the literature (4, 5, 7-9)

References

  • Order all references at the end of the paper in numerical order if citing by number (superscript or italics).
  • Order all references at the end of the paper if citing by Author-Date in alphabetical order by first author's last name.
  • Using a hanging indent for any second and subsequent lines in your reference.
  • When citing an online source, indicate [Online] after title and include URL and access date.
  • Different formats have slightly different rules for citation. See How do I cite section on the left-hand side. 

 

The above text was created by Sheridan College Library and can be located here.

Why Cite? When to Cite?

Why we cite

When we write a paper, we gather background information and build arguments drawing on the work, knowledge, ideas, expressions, and reportings of others.

This information is found in many places -- journal articles, books, YouTube videos, blogs, maybe even in an email. Whatever the source, we are required to acknowledge who or what that source is when we refer to the work in our own.

We may refer to another person's work for many reasons. These include:

  • setting the stage for your position on a topic;
  • demonstrating support for an idea by another person;
  • demonstrating an opposing viewpoint.

When we cite

Citations create necessary links, directing your reader to the source you're crediting. We make an in-text citation that links to our reference list at the end of our document, which then links to the original source.

For this reason, when we talk about citations, we're talking about two different instances, once in the body of our text -- In-text citations -- once at the end of our text -- the reference list.

How we cite

When using ACS, the in-text citations are commonly denoted with a superscript marker (raised number) at the end of the sentence or piece of information that is being pulled from the reference. The superscript number is repeated for each time that same reference is used, and then it is tied to the same number in the reference list for that full citation. 

The 2020 edition of the ACS Guide does outline additional ways of creating in-text referencing. Superscripts are still a preferred method, but parenthetical referencing and author-date referencing are other options (see section 4.3.2). 

 

The above text was created by Arielle Lomness at the University of British Columbia (UBC) Library and is being shared with permission. You can locate the original resource here.

Additional ACS Resources

There are numerous excellent online resources on how to format ACS citations, here are a few of them: