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American Chemical Society (ACS) Style Guide

If you use author-date in-text citations, order your references list alphabetically by the last name of the first author. For multiple references with the same author or first author, list the single-author references first, then the two-author citations, and the group citations last.

Order of Works with Same First Author

  • Single-author: arrange chronologically (earliest one first)

    Hamilton, F. J. Biochemistry 2003, 42, 78-86.
    Hamilton, F. J. J. Agric. Food Chem. 2004, 52, 1622-1633.

  • Same author(s) and same date: arrange chronologically (as accurately as possible) and add lowercase letters a, b, c, immediately after the date in the parentheses.

    Hamilton, F. J. J. Agric. Food Chem. 2004a, 52, 1622-1633.
    Hamilton, F. J. J. Org. Chem. 2004b, 69, 298-306.

  • Same first author, but different co-authors: come after the single-author entries for the first author and then chronologically.

    Scarponi, T. M.; Moreno, S. P. Biochemistry 200241, 345-360.
    Scarponi, T. M.; Adams, J. S. J. Pharm. Sci. 2003, 92, 703-712.

Order of Works by Authors with Same Last Name

Alphabetize by first initial.

Moher, J.
Moher, M., & Feigenson, L.

Order of Works by Group Authors

Alphabetize by the first significant word; do not abbreviate name.

Moher, J.
National Institute of Mental Health.
Oliver, M. B.