Citation methods vary depending on the style guide that the paper is following; however, every quote in a paper should include an in-text reference that shows the quote's source. Colleges typically require students to use either the American Psychological Association or the Modern Language Association citation style.
Under APA style, quotes should include the authors' surnames, the years of publication and the page numbers for the sources. Quotes of up to 40 words should be enclosed in quotation marks, with the source information at the end of the sentence: "Citation is simple" (Robinson, 2001, p. 32). The information may be broken up to help the reader; for example: Robinson (2001) believes that "citation is simple" (p. 32).
Longer quotations are written as separate paragraphs with indentations and no quotation marks. The authors, years and page information are included at the end of the quotes.
All of the sources are listed in the reference list at the end of the paper. The information is formatted depending on the source, so a book's entry on the list includes different information than a website's entry.
In-text citations in MLA style are formatted similarly; however, the year of publication is not necessary: "MLA style does not require 'p.' either" (Robinson 34). Again, the author's name and page number may be included separately if the quote is at the beginning of a paragraph. The MLA system also allows for bibliographic footnotes that suggest other sources in which the reader may be interested.
Both styles have their own guidelines for sources that have multiple authors, sources that do not have page numbers and other situations that can arise.