Reference Components


List authors in the order used in the work, using last names or family names followed by initial(s). Refer to Print Publications – Books in this guide for formatting of multiple authors or editors. If an author is unknown, move the title to the author position at the front of the reference, and use the title to alphabetize the work.


Unless otherwise noted, only the year of publication or production is needed. If the date is unavailable, use the abbreviation (n.d.) for no date.


In the title of a work only the first word and proper nouns are capitalized. All words in the title of a periodical (journal, newspaper, etc.) should be capitalized. Note in the examples when a title is italicized.


DOIs and URLs are included in references for digital publications. When possible, use the digital object identifier (DOI). The DOI is a permanent and unique combination of numbers and letters assigned by a publisher that can be used to locate a work online, even if it moves. In a reference, format the DOI as “doi:xxx” where the numbers and letters of the DOI replace xxx. For example: doi:10.1103/PhysRevD.15.2752 In the reference "doi" is written in lower case letters.

If no DOI exists for a book or article, provide the home page URL of the book publisher or the journal. For example, the URL for an article in Clinical & Investigative Medicine would read: "Retrieved from". When referencing journal articles you may need to search the web for the journal title to find the home page. If a work cannot be located online through the publisher, give the URL for the home page of the website or database you used to access the work. Never include the Carleton proxy ( in the URL.

For other web references, provide the full URL. When using multiple website sub-pages, provide the URL for the home page. In a reference, format a URL as “Retrieved from”. For example: Retrieved from

Content last reviewed: August 2, 2018