This guide provides a brief introduction to American Chemical Society (ACS) Style and supporting resources. For more additional examples of ACS references and citations, please consult the ACS Style Quick Guide or The ACS Style Guide in our Reference Collection.
A reference consists of two main components:
When you reference another source in the body of your paper, use an in-text citation. This gives credit to the original source of an idea and refers to the reference in your bibliography at the end of your document.
Your instructor may ask you to form in-text citation by authors' names or by number. Always check with your instructor to confirm which convention your class is using.
Also known as Author-Date, citing by name requires the inclusion of the author or authors' name and the date of publication. References at the end of your document should then be arranged alphabetically by the author's last name.
Basic Format:
(Author's Last Name(s) or Organization, Year)
(Morelli and Scholkmann, 2023)
I am...
In ACS Style, it is preferred that you paraphrase and summarize from a research article rather than quoting the author's words directly. Always include the last name of the author(s) and the year of the publication, so your reader can find the full citation in the reference list.
According to Morelli and Scholkmann (2023), the role of lipids in oxygen absorbtion is critical for many aerobic species. Further, each species' gas exchange system has evolved to meet specific environmental, anatomical, and physiological needs (Jürgens and Gross, 2002).
If you're quoting the exact words of someone else, introduce the quote with an in-text citation in parentheses. Any sentence punctuation (e.g. commas, periods, etc.) should be placed outside the quotation marks or after the in-text citation unless included in the original quotation.
Note: The ACS Style Guide does not provide specific guidelines for identifying or including page numbers in in-text citations. However, a specific journal or your instructor may require the inclusion of page numbers when directly quoting from a source. Always confirm with your instructor before submitting your work.
When citing a passage longer than three sentences or 50 words, use a block quote.
Morelli and Scholkmann (2023) contend:
It seems unlikely that the way developed during evolution to accomplish the adjustment of ATP production to neuronal activity is the detour of first increasing CBF, which then ‘passively' drives an increased ATP production by increased oxygen delivery. Such a regulation would introduce a high vulnerability of brain function depending totally on intact neurovascular coupling.
Toro Tip: Use direct quotes sparingly! Focus on summarizing the findings from multiple research studies. In the sciences, only use the exact phrasing or argument of an individual when necessary.
In-text citations differ depending on the number of authors listed for a work, and if there is a group author.
I'm citing a work with...
You only need the author's last name and the year in parentheses. Separate with a comma.
(Abrams, 2018)
List both authors' last names, connected with 'and,' and the year. Separate the authors' names from the year with a comma.
(Wegener and Petty, 1994)
If there are more than two authors use et al., which means "and others," a comma and the year.
(Harris et al., 2018)
Groups or organizations may be the author of a resource. Acronyms for well-known organizations may be used. Otherwise, the full name of an organization should be used. Regardless, the in-text citation author should match the end reference.
(Centers for Disease Control and Prevention, 2013)
or
(CDC, 2013)
You may be asked to cite using a numerical convention where you refer to items in your bibliography either by using a number within parentheses (1) or in superscript1.
If using this format, references in your bibliography are number sequentially. If a reference is repeated, use the original number rather than giving it a new number.
In-Text Citation:
The role of lipids in oxygen absorption is critical for many aerobic species.1 Further, each species' gas exchange system has evolved to meet specific environmental, anatomical, and physiological needs.2
The role of lipids in oxygen absorption is critical for many aerobic species (1). Further, each species' gas exchange system has evolved to meet specific environmental, anatomical, and physiological needs (2).
References:
1. Morelli AM, Scholkmann F. The significance of lipids for the absorption and release of oxygen in biological organisms. Adv Exp Med Biol. 2023;1438:93-99. https://doi.org/10.1007/978-3-031-42003-0_16
2. Jurgens KD, Gross G. Phylogeny of gas exchange systems. AINS. 2002;37(4):185-195. https://doi.org/10.1055/s-2002-25080
Include the complete citation at the end of your paper in a References section. References in Citation-Name and Name-Year systems are organized by the author's last name in alphabetic (A-Z) order. References in Citation-Sequence systems should appear in the order of assigned superscript number. Use an hanging indent to separate each list item.
I'm citing a...
Roppongi, T; Mizuno, N; Miyagawa, Y; Kobayashi, T; Nakagawa, K; Adachi, S. Solubility and Mass Transfer Coefficient of Oxygen Through Gas- and Water-Lipid Interfaces. J. Food Sci. 2021, 86 (3), 867–873. DOI: 10.1111/1750-3841.15641
Online Publication:
Kenkel, C. D. Want to See Coral Reefs Grow? Freeze Them. The New York Times (New York, NY), August 15, 2024, updated August 15, 2024. https://www.nytimes.com/2024/08/15/opinion/caribbean-coral-reefs-climate-change.html (accessed 2024-08-19).
Online Publication (Accessed through database):
Kenkel, C. D. Want to See Coral Reefs Grow? Freeze Them. The New York Times (New York, NY), August 15, 2024, updated August 15, 2024, A19. http://libproxy.csudh.edu/login?url=https://www.proquest.com/newspapers/want-see-coral-reefs-grow-freeze-them/docview/3093731911/se-2?accountid=10347 (accessed 2024-08-19 from ProQuest News & Newspapers).
It's important to identify whether you are citing an authored book or an edited book. If the book maintains the same author(s) throughout the whole book, it should be cited as an authored book.
Authored Whole Book Reference:
Russel, K.; Sheppard, C. Coral Reefs: A Natural History; Princeton University Press, 2021.
Russel, K.; Sheppard, C. Coral Reefs: A Natural History; Princeton University Press, 2021. DOI: 10.2307/j.ctv1h9dh6q
Authored Book Chapter Reference:
Russel, K.; Sheppard, C. Different Kinds of Reefs. In Coral Reefs: A Natural History; Princeton University Press, 2021; pp 60-95.
Russel, K.; Sheppard, C. Different Kinds of Reefs. In Coral Reefs: A Natural History; Princeton University Press, 2021; pp 60-95. DOI: 10.2307/j.ctv1h9dh6q.6
If the book's chapters are written by different authors and was compiled by editors, then it should be cited as an edited book.
Whole Edited Book Reference:
Biodiversity and Climate Change: Transforming The Biosphere; Lovejoy, T. E., Lee, H., Eds.; Yale University Press, 2021.
Chapter in an Edited Book Reference:
Parmesan, C. Range and Abundance Changes. In Biodiversity and Climate Change: Transforming the Biosphere; Lovejoy, T. E., Lee, H., Eds.; Yale University Press, 2021; pp 25-38.
Reference:
U.S. Environmental Protection Agency. Basics of Climate Change. https://www.epa.gov/climatechange-science/basics-climate-change (accessed 2024-08-19).
Reference:
Bishop, R.; Erdman, M. M.; Fields, P.; Fullerton, K.; Jackson, K.; Mahon, B.; National Enteric Disease Surveillance: Salmonella Surveillance Overview; Centers for Disease Control and Prevention, National Center for Emerging and Zoonotic Infectious Diseases: Atlanta, GA, 2011. https://www.cdc.gov/nationalsurveillance/PDFs/NationalSalmSurveillOverview_508.pdf (accessed 2024-08-19).
Thesis or Dissertation (accessed online)
Valentin, E. R. Narcissism Predicted by Snapchat Selfie Sharing, Filter Usage, and Editing. M.A. Thesis, California State University Dominguez Hills, Carson, CA, 2019. https://scholarworks.calstate.edu/concern/theses/3197xm925?locale=en (accessed 2024-08-19).
Thesis or Dissertation (in print)
Valentin, E. R. Narcissism Predicted by Snapchat Selfie Sharing, Filter Usage, and Editing. M.A. Thesis, California State University Dominguez Hills, Carson, CA, 2019.
1. Highlight the citaiton with your cursor.
2. Right click.
3. Select Paragraph.
4. Under Indentation, select Special and Hanging.
Microsoft Word and Google Docs have a Format Painter tool that will copy and apply basic formatting to any text!
1. Highlight the formatting you want to apply.
2. Select Format Painter.
3. Highlight the text you want to change.
Note: If using the Format Painter on the Reference List, you'll need to go back and add italics.
This guide was created by Aric Haas at CSUDH Library and licensed under a Creative Commons Attribution-NonCommercial-Share Alike 4.0 International License.