Citation Guide

Parenthetical Citations in the Body of the Paper

When you quote or paraphrase from a source (book, article, or webpage) in your paper, you need to insert an in-text citation. 

In ACS papers, references can be cited in text in three different ways.  Ask your instructors which method they prefer!

1.  Superscript numbers

At the end of the cited information, outside the period:
Van Arnum states, "Continuous-flow technology offers potential advantages compared with traditional batch manufacturing of pharmaceuticals."¹

Within the cited information:
Van Arnum¹ discusses the advantages of continuous-flow technology.

Once a source has been cited, the same number is used in all subsequent references.

2.  Italicized numbers in parentheses

At the end of the cited information, inside the period:
Van Arnum states, "Continuous-flow technology offers potential advantages compared with traditional batch manufacturing of pharmaceuticals" (1).

Within the cited information:
Van Arnum (1) discusses the advantages of continuous-flow technology .

3.  Author name and year of publication in parentheses

At the end of the cited information:
 "Continuous-flow technology offers potential advantages compared with traditional batch manufacturing of pharmaceuticals" (Van Arnum, 2013).

Within the cited information:
Van Arnum (2013) discusses the advantages of continuous-flow technology.

 

Rules

Numerical Reference Methods (Superscript or Italicized)

  • Start with 1 and number consecutively throughout the paper.
  • If a reference is repeated later in the paper, do not give it a new number; use the original reference number

Author Name and Year Parenthetical Reference Method

  • For a source/reference with two authors, include both last names joined by the word and: (Mars and Grande, 2014)
  • If a source/reference has more than two authors, include only the first author listed followed by et al. (always use a period after al!): (Smith et al., 2013)

Citing More Than One Reference at a Time

Numerical Methods: 

List numbers in ascending order. Separate numbers with commas, or, if they are part of a consecutive series, use a dash to indicate a range.

in the studies.¹-²

in the literature (2, 4, 8-10)

Author-Year Method:

List the references/sources alphabetically by author's name.  Use a semicolon to separate individual references.

(Mars and Grande, 2014; Smith, 2013)

Quotation Length:

If you are using a quotation with 50 words or more, indent on both sides to make a narrow column. Do not use quotation marks.