The Author-Date style was developed primarily for use in the "physical, natural, and social sciences, and is recommended by Chicago for works in those areas" (Chicago Manual of Style 2017, 893). It has two major differences compared to the Notes and Bibliography Style:
The latter change is because the subject areas mentioned above generally place greater importance on the recentness of a source compared to other subjects in the humanities.
Like the Notes and Bibliography style, the reference list (commonly titled "References" or "Works Cited" in Author-Date style) is included at the end of the paper, lists all sources cited in the paper in alphabetical order, and contains more publication details than the in-text citations.
The following tabs on this page present examples, templates, and brief explanations for the proper use of Author-Date style. More detailed information about the use of the Author-Date style can be found:
Place the author's last name, date, and page number within brackets in the text. The citation is placed after the quote or paraphrased material and before the punctuation marking the end of the sentence. Pay attention to the placement of punctuation in the following examples.
"your quote here" (Lerner 2009, 99).
Place "and" between the two authors' names.
Your paraphrased sentence here (Ward and Burns 2007, 52-54).
*note: to cite a page range, include a dash between the start page and end page as shown above.
Place "and" before the final listed author's name.
(Jacobs, Thomas, and Lang 1997, 65, 69).
*note: to cite nonconsecutive pages in a single citation, separate the page numbers with a comma as shown above.
Include the name of the first listed author followed by "et al." starting from the very first time the source is cited.
(Secher et al. 1996, 276).
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
The only difference between Notes and Bibliography and Author-Date with regard to bibliography entries is the placement and formatting of the year - Author-Date places the year immediately after the authors' names and does not put brackets around it. Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name) as shown in the examples below.
Last name, First name M., and First name M. Last name. Year. "Title of Article." Journal Title volume, no. issue (issue month/season, if applicable): first page - last page. doi.
Kossinets, Gueorgi, and Duncan J. Watts. 2009. "Origins of Homophily in an Evolving Social Network." American Journal of Sociology 115, no. 2: 405-50. http://doi.org/10.1086/599247.
Use a URL instead of a DOI.
Whitney, Frank P. 1929. "The Six-Year High School in Cleveland." School Review 37, no. 4: 267-71. http://www.jstor.org/stable/1076243.
List all of the authors' names.
Fulcher, Karyn, Meriah Drabkin, Jennifer Gibson, Jenny Francoeur, Abbey Eurchuk, Maria Weaver, Bobbi Turner, and Nathan J. Lachowsky. 2021. "Contraceptive decision-making and priorities: What happens before patients see a healthcare provider." The Canadian Journal of Human Sexuality 30, no. 1: 56-64. http://muse.jhu.edu/article/791387.
List the first seven authors followed by "et al."
Anand, Sonia S., Sylvia Abonyi, Laura Arbour, Jeff Brook, Sharon Bruce, Heather Castleden, Dipika Desai et al. 2018. "Canadian Alliance for Healthy Hearts and Minds: First Nations Cohort Study Rationale and Design." Progress in Community Health Partnerships: Research, Education, and Action 12, no. 1: 55-64. http://doi.org/10.1353/cpr.2018.0006.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
The only difference between Notes and Bibliography and Author-Date with regard to bibliography entries is the placement and formatting of the year - Author-Date places the year immediately after the authors' names and does not put brackets around it. Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name) as shown in the examples below.
Last name, First name, and First name last name. year. Title of Book, number of edition. Place of publication: Publisher.
Lerner, Fred. 2009. The Story of Libraries: From the Invention of Writing to the Computer Age, 2nd ed. New York: Continuum.
Jacobs, Sue-Ellen, Wesley Thomas, and Sabine Lang, eds. 1997. Two-Spirit People: Native American Gender Identity, Sexuality, and Spirituality. Urbana: University of Illinois Press.
Sechzer, Jeri A., Sheila M. Pfafflin, Florence L. Denmark, Anna Griffin, and Susan J. Blumenthal, eds. 1996. Women and Mental Health. Baltimore: John Hopkins University Press.
Begin with the title instead of the author.
A True and Sincere Declaration of the Purpose and Ends of the Plantation Begun in Virginia, of the Degrees Which It Hath Received, and Means by Which It Hath Been Advanced. 1610. London.
Ellet, Elizabeth F. L. "By Rail and Stage to Galena." In Prairie State: Impressions of Illinois, 1673-1967, by Travelers and Other Observers, 1968. Edited by Paul M. Angle, 271-79. Chicago: University of Chicago Press.
Whitman, Walt. Leaves of Grass. 1855. New York. http://www.whitmanarchive.org/published/LG/1855/whole.html.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
The only difference between Notes and Bibliography and Author-Date with regard to Bibliography entries is the placement and formatting of the year. Author-Date places the year immediately after the authors' names and does not put brackets around it.
Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name) as shown in the examples below.
Author's name or Corporation name. Year of publication. "Title of Webpage." Title of Website. Type Out Website Abbreviations Where Necessary. Full publication or accessed date, http://www.URL.com
Brown, James Robert and Yiftach Fehige. 2023. "Thought Experiments." Stanford Encyclopedia of Philosophy. Last revised November 28, 2023. https://plato.stanford.edu/entries/thought-experiment/
Roberts, Alexander, and James Donaldson, eds. n.d. "ANF01. The Apostolic Fathers with Justin Martyr and Irenaeus: Introductory Note to the Epistle of Mathetes to Diognetus." CCEL, Cristian Classics Ethreal Library. Accessed April 23, 2011. http://www.ccel.org/ccel/schaff/anf01.iii.i.html.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15.50-15.52 "Websites, Blogs, and Social Media"
The only difference between Notes and Bibliography and Author-Date with regard to bibliography entries is the placement and formatting of the date - Author-Date places the date immediately after the authors' names and does not put brackets around it. Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name) as shown in the examples below.
Cleese, John, Terry Gilliam, Eric Idle, Terry Jones, and Michael Palin. 2001. "Commentaries." Disc 2. Monty Python and the Holy Grail, special ed. DVD. Directed by Terry Gilliam and Terry Jones. Culver City, CA: Columbia Tristar Home Entertainment.
Curtis, Michael, and Gregory S. Malin. September 19, 1996. "The One with the Princess Leia Fantasy." Friends, season 3, episode 1. Directed by Gail Mancuso. Burbank, CA: Warner Home Video.
Harwood, John. August 23, 2008. "The Pros and Cons of Biden." New York Times video, 2:00. http://www.nytimes.com/video/us/politics/1194817091987/the-pros-and-cons-of-biden.html?module=Search&mabReward=relbias%3Aw.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
The only difference between Notes and Bibliography and Author-Date with regard to bibliography entries is the placement and formatting of the date - Author-Date places the date immediately after the authors' names and does not put brackets around it. Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name).
Truman, Harry S. April 16, 1945. "First Speech to Congress." Transcript and Adobe Flash audio, 18:13. Miller Centre of Public Affairs: University of Virginia. http://millercenter.org/scripps/archive/speeches/detail/3339.
Stan Rogers. 1981. "The Idiot." MP3 audio. Track 6 on Stan Rogers, Northwest Passage. Fogarty's Cove Music.
Note: "MP3 audio" can be replaced with "Spotify," "Apple Music," etc. The rest of the citation remains the same.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
The only difference between Notes and Bibliography and Author-Date with regard to bibliography entries is the placement and formatting of the date - Author-Date places the date immediately after the authors' names and does not put brackets around it. Note also that the first author's name in any bibliography entry is inverted (Last name, First name Middle name) and subsequent names are not inverted (First, Middle, then Last name) as shown in the examples below.
Last name, First name. Date of Publication. "Title of Article." Magazine/Newspaper Name. Link (if applicable).
Frank, Michael. August 2009. "La Concha Revival: San Juan's Tropical Modernist Gem Makes a Comeback." Architectural Digest. 103-4.
Masters, Coco. December 17, 2006. "The Takeaway Diet of 2006." Time.
http://content.time.com/time/magazine/article/0,9171,1570794,00.html.
Borzi, Pat. January 25, 2010. "Retirement Discussion Begins Anew for Favre." New York Times. http://www.nytimes.com/2010/01/26/sports/football/26vikings.html?emc=etal.
For more details, consult the Chicago Manual of Style, 17th Edition, Section 15 ("Author-Date References").
Images should be cited in a caption below the image itself. Label it with Figure # or Fig. # so you can clearly refer back to it in the main text of the paper (e.g. "As shown in Figure 4,...")
Remember to cite the source you are using to view the image. If you saw it in a book, cite the book. If you are looking at the original work, cite the original work.
Fig. 1. Artist first and last name, Title of work. Year of original art, Medium (e.g. Oil on canvas, drawing, sculpture, photograph, etc.), Measurements (e.g. 18.5 x 12 cm). Location of original museum, province, country. Available from: Database name, www.URL.com (accessed month day, year).
Example
Database: Fig. 1. Rogier van der Weyden, Saint Catherine of Alexandria. 1430-1432, Diptych panel, 18.5 x 12 cm. Kunsthistorisches Museum, Vienna, Austria. Available from ARTstor, http://artstor.org (accessed September 30, 2009)
Figure 1. Author first and last name, Title of work. Year of original work, medium, dimensions. From: Author of book, Title of book. City: Publisher, year. Page or plate number.
Example
Fig. 1. Pierre-Auguste Renoir. Young girl and a cow at Saint-Briac. From Judy Le Paul Gaugin and the Impressionists at Pont-Aven. New York: Abbevill Press. 1987. Page 137.
Note: for books, use the year the book was published so the reader can find the source that you used. Do not put the year the original image was created.
Fig. 1. Kostyantyn Steblovskyy. Swanlike End. 2015, Digital Image. Available from: National Geographic. http://photography.nationalgeographic.com/photography/photo-of-the-day/swan-lake-bled/ (Accessed October 14, 2015).
Found a great image on Facebook or Twitter? Trace the image back to its original website and cite it as a web page. Using a profile picture or mobile upload? Make a note in this format:
Creative commons image citations look different because they are copyrighted differently. By indicating the CC info (e.g. CC BY 2.0) the reader is able to know if the image can be shared, modified, and/or sold. For example, CC BY 2.0 means that anyone is able to share and adapt the image for personal or commercial use so long as the original author has been credited and any changes have been noted. The original author is not able to change these rights as long as these rules have been followed.
Template
Title of work by Author or screen name is licensed under CC info
Example
Creative Commons 10th Birthday Celebration San Francisco; by tvol is licensed under CC BY 2.0. https://www.flickr.com/photos/sixteenmilesofstring/8256206923/in/set-72157632200936657
Information regarding Creative Commons citing came from the following source:
"Best practices for attribution”. Creative Commons Wiki. Last modified March 4, 2014. https://wiki.creativecommons.org/wiki/Best_practices_for_attribution
This information comes from page 905 of the Chicago Manual of Style, 17th edition. If you have any further questions, talk to your instructor.
For quotes with 100 words or more, format your quotation as follows:
Create a freestanding block, separated from the paragraph with the quote starting on a new line, and indent all lines of the paragraph about 0.5 inches from the left margin. Do not use quotation marks, unless there is a quote within your quote. Unless the paragraph ends following the quote, continue the paragraph with no indentation.
The in-text citation for a block quote in the Author-Date style is placed after the final punctuation of the quote, not before it as with other quoted/paraphrased material. The information in the citation remains the same, as shown in the example below:
Note that, although many Chicago papers use single-spaced block quotations, page 69 of the Chicago Manual of Style, 17th Edition states that "Prose extracts should have the same line spacing as the surrounding text." Check with your instructor to be sure about spacing requirements on assignments.