Sources: How to Cite Sources: Citation Formats

Table of contents

How to cite sources

From sources to citations

Sources types

Fields

Citation formats

Citation styles

PREFERRED FORMATS for citations may vary among different scholarly disciplines, departments, or even among instructors within the same discipline. You should become familiar with the three most widely used citation formats:

•	the parenthetical format used especially in the social sciences;
•	the author-date format widely used across the social and natural sciences;
•	and the note format (footnote or endnote) used by both scientists and humanists.

Before selecting a format, examine common journals in your discipline or consult with your instructor.
Each of these citation formats includes two basic elements. A succinct marker placed in the text, either a text citation enclosed in parentheses or a note number, informs the reader that you are citing a specific source at this point in your paper. Each marker points to the full citation, located either in a List of Works Cited at the end of your paper or in the note, that provides the complete map required for the reader to locate the source.

Parenthetical and author-date formats

Contents of text citations The parenthetical style shortens text citations, providing only enough information to enable readers to locate the source in the List of Works Cited. Usually only the author's last name and page number appear in the text citation: "(Hurston 33)." If the author's name is mentioned in the text, only page numbers are included: "According to Hurston (33)." If the list of sources includes more than one work by an author, a short version of the title is also given: "(Hurston, Dust tracks 14)." For sources with no authors or with corporate authors (e.g., the U.S. Congress, House Committee on Commerce, Subcommittee on Health and the Environment), use only a short version of the title: "(Health care 14)." No commas are placed before page numbers.
The author-date style adds dates to text citations: "(Hurston, 1984, p. 33)," "According to Hurston (1984, p. 33)." This slightly lengthens the parenthetical intrusion in your text; yet many disciplines where timeliness of research is important prefer to emphasize dates. If your sources include several works by the same author with the same year of publication, place lowercase letters — a, b, c, etc. — immediately after the year in the text citation to distinguish the various titles: "(Hurston, 1995a, p. 14)." The author-date text citation also employs more elaborate punctuation than does the parenthetical format.

Placement of text citations As a general rule, always try to introduce your initial use of a quoted or paraphrased source by mentioning the author's name or the work's title in your text. When your own prose clearly specifies such items, the parenthetical marker can simply include the source's page number(s):

As Ernest Jones argues in Hamlet and Oedipus (90–102), Hamlet loves his mother and ...

When placing a text citation after a short quotation (five lines or fewer), the marker comes after the closing quotation mark and before the punctuation ending the quotation. When the quotation itself ends on a question mark or exclamation mark, place such punctuation within the quotation and follow the marker with a period:

"Why should not we also enjoy an original relation to the universe?" (Emerson 21).

For long quotations (six lines or more, set off from your text by starting a new line and indenting one-half inch from the left margin, no quotation marks), the text citation comes after the final punctuation mark of the quotation.
For paraphrases and other uses of sources, place the parenthetical marker immediately following the text being cited, even if in the middle of your sentence (but usually at the end of a phrase). Such placement helps the reader to distinguish between the paraphrase and your own remarks.

According to a well-known anthropologist, we should define a culture not by its notable customs but by the ways it specifically works to govern how its members act (Geertz 44), a definition that can help us revise our usual understanding of a primitive culture's "ignorant" or "superstitious" religious beliefs, for example.

Full citations Both the parenthetical and the author-date formats require a List of Works Cited to be appended to your paper, providing full citations for all sources cited. The parenthetical format alphabetizes the citations by authors' last names and then by title, ignoring any initial articles.
The author-date format alphabetizes by author's last names and then by date. For several works by a single author with the same publication date, alphabetize by title (unless the chronology of publication can be determined, for example, in sources such as newspapers).

Note formats

If your work makes use of many sources, as do advanced research papers or theses, multiple parenthetical citations can disfigure your text and distract readers from your argument. In a sentence, for example, three parenthetical citations would be more visually awkward than three numerical citations — or indeed than one numerical citation at the end of the sentence.
Furthermore, notes allow you to add relevant but not necessarily essential information to your main argument, to qualify your argument or to alert your reader to (and not incidentally, to demonstrate your awareness of) other views on your topic. Even when you use the parenthetical or author-date format of citation, you may also wish to resort periodically to such supplementary notes in order to take advantage of this format's additional power to convey information.
As the names imply, endnotes appear after the text, starting on a new page. Footnotes appear at the bottom of pages where their markers occur. Most word processing software includes tools for preparing and formatting endnotes and footnotes.

Placement of note numbers Place note numbers at the same points in your text as you would the text citations in the parenthetical or author-date formats. However, unlike those formats, the superscripted note numbers always follow all punctuation marks, except dashes. To avoid interrupting the continuity of your text, generally place note numbers at the end of a sentence or a phrase containing the material being cited.
Number your notes consecutively throughout your paper, starting with 1. For a thesis or a long paper divided into sections or chapters, you may want to renumber the notes (especially if you are using footnotes), starting with 1 for each section. Do not begin a new sequence on each separate page. Always use Arabic numbers, and not asterisks or other symbols, as note markers. Most word processors can automatically insert sequential note numbers for you.
The Science style of notes (always endnotes) employs a different system of numbering. Notes are numbered sequentially throughout the paper; but if any once-cited source is cited again, the original note number is simply repeated at the point of the subsequent citation. Each source is listed only one time. Hence, Science endnotes function essentially as a numbered (rather than alphabetized) List of Works Cited, each of which is cited by number in the text.

Form and content of notes All notes are indented. Most word-processors automatically provide the superscripted note number, after which you type the note.
The arrangement of fields and punctuation in notes differ in two significant ways from that in the List of Works Cited used in parenthetical and author-date formats. In the note format, you write the author's name in normal (rather than reversed) order. And in the note format, you separate major divisions by commas (rather than periods). A note for a journal article would thus be arranged as follows:

¹⁰⁷ Chorng-Yuan Hwang, "An Inverse Compton Process for the Excess Diffuse EUV Emission from the Virgo and Coma Galaxy Clusters," Science 278 (1997), 1917–19.

Subsequent footnotes to the same source can simply include the author's last name (or a shortened title of the work if you elsewhere cite another source by the same author) and the pages, separated by a comma. Do not use Latin abbreviations like "ibid.," "op. cit." or "loc. cit." to perform this function.

¹⁰⁸ Hwang, 1917–19.

List of works cited Such a list may not necessarily be required for the note format. Check for your instructor's preference. If you do include a List of Works Cited, it should begin on a new page, at the very end of your paper (i.e., after the endnotes if you're using that format). In a long paper with notes, you should include a List of Works Cited so that readers can identify a full citation more easily than paging through dozens (or hundreds) of notes.