Parenthetical citation is used when citing a source in the body of your text. The source of your information must be clearly written out between parentheses at the end of a sentence, although the exact information needed will depend on the nature of your sources. When available, use the last name of the author followed by a space and the page number --- for example, (Smith 244). If you specifically mention the study in the body of your work, you can use only page numbers. List the names of the authors in alphabetical order, separated by a comma, if the source has up to three different authors. For a source with more than three authors, list the name of the first author followed by the term "et al." If the author of the source is unknown, replace the author's name with the title of the source. In-text citations must correspond to an entry on your works cited page.
In MLA format, long quotations (more than four lines) are indented one inch from the left margin. Citations for these and shorter quotations must appear immediately after the quotation. Quotations shorter than four lines are cited exactly the same as in-text citations, but the citation of longer quotations, while the same in form, differs in placement. The citation of a long quotation comes after the final period and has no period after the final parenthesis.
Cite books by first listing the name of the author (last name before first name, separated by a comma) followed by a period, then the title of the book in italics followed by a period, then the place of publication followed by a semicolon, then the name of the publisher followed by a comma, then the year of publication followed by a period and finally list the medium of publication (for books, print) followed by a period. Many different rules exist for different types of books such as translated books, multivolume books and the like. The MLA Handbook for Writers of Research Papers and the Purdue Owl website can tell you exactly how to format these strange cases.
When citing a newspaper or scholarly article, list the name of the author, the title of the article in quotes, the name of the periodical in italics, the day (if available), month and year (date units should not be separated by commas), the pages followed by a period, and the medium of publication. Most scholarly articles don't list day or month, but instead list an issue number and/or a volume number.
Articles found online are cited in the same manner as periodicals with the addition of the date that you last accessed the material. Although the MLA no longer requires a URL attached to a citation, a teacher or professor may. Always make sure you check with your teacher about her specific citation guidelines before working on a research paper.