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Run-On Sentences

Run-on sentences occur when writers try to combine more than one idea into a single sentence. They cause confusion because readers are not sure when one idea ends and the next one begins. Read our entry and test your knowledge with our quiz!

APA Citations

The American Psychological Association (APA) produces a style manual that lists rules for how writers in the social sciences should format their work. These rules standardize writing, provide credit to sources, and help readers locate source material. 

This is a brief guide to writing citations in APA style.  Page numbers will refer to the APA Publication Manual, 6th edition. Please see our other pages on APA Style for more information on formatting your paper and writing references.

We'll first begin by explaining why citation is important through a look at plagiarism. Then we'll show you how to add citations after quotes and paraphrases. Afterward, we'll go over a few special cases that you may run into that require a slightly different approach. Use the links below to skip to individual sections of this article. 

  1. Plagiarism and Self-Plagiarism
  2. Quoting
  3. Paraphrasing
  4. Citation: Special Cases
  5. Direct Quotation of Online Material without Page Numbers
  6. Accuracy of Quotations
  7. Ellipses
  8. Inserting Material
  9. Citations within a Quotation
  10. Permission to Quote, Reprint, or Adapt
  11. Multiple Authors and Multiple Works 
  12. Author Has Multiple Works from the Same Year
  13. One Work with Two Authors
  14. Three or More Authors
  15. Multiple Authors with the Same Last Name
  16. Several Passages from the Same Author in a Row

Plagiarism and Self-Plagiarism

APA Citation rules exist to prevent plagiarism and give credit to sources. Plagiarism occurs when writers use writing, research, or ideas without providing credit to the original author. 

Self-plagiarism is when a writer uses his/her old work, but presents it as new. This is bad practice because the new document should be an original work, and should only draw upon an author's older work to provide context.


Quotations must be reproduced word-for-word from the original source. Each quotation must be immediately followed by an in-text citation. Citations include the author's last name (or title if no author is listed), year of publication, and page or paragraph number where the quote appears (p. 170).

(Author last name, Year, page number)

You’ll also need to include a complete reference for the source in the reference list. If you end the quotation in the middle of the sentence, place the citation there and continue the sentence (p.171).

Use block quotations when your quote is 40 words or longer. They begin on a new line, indented a half inch from the left margin, without quotation marks. Include the complete citation unless the author’s name has already appeared on the page, in which case you can omit the author’s name (p.171).


See our page on paraphrases for help on how to compose a paraphrase. The APA recommends that citations for paraphrases include a page or paragraph number (p.171).

Citation: Special Cases

Sometimes, you’ll need to alter a quotation or include other information. The most common reasons are listed below.

Direct Quotations of Online Material without Page Numbers

If the website doesn’t include pagination, make do with what you have. Use paragraph numbers if listed (for example, para. 4). If not, cite the heading it appears under and the paragraph number under the heading. If there are no headings, use a short title enclosed in quotation marks (p. 172).

Accuracy of Quotations

Use [sic ] after any error made by an author of a quotation (p.172).


Use three ellipsis points (. . .) to omit material from a quotation. If the omission covers multiple sentences, use four points (pp. 172-173).

Inserting Material

Use brackets [like the ones surround these words] to add explanations or clarifications inside quotations (p. 173). 

Citations within a Quotation

Leave these in your text, but do not include them in your list of references (p.173).

Permission to Quote, Reprint, or Adapt

If you use a lot of information from a particular author or work, you may need to seek permission to reproduce it (p. 173): 

  • more than three figures or tables from a book chapter or journal article
  • single text abstracts that are more than 400 words
  • several text abstracts that equal more than 800 words

Individual copyright holders will have their own rules, so it is your responsibility to find them out and follow them. If you do receive permission, use a footnote to acknowledge it (p. 174).

Multiple Authors

Context plays a big role in determining how much information you need to include in a citation. APA internal citations normally include the author’s name, publication year, and the page number of the text being referenced, placed between a pair of parentheses:

(Martin, 1996, 457)

Author Has Multiple Works from the Same Year

If the author has multiple works from the same year in your references list, also add a letter after the year. This will designate that you’re referring to the first publication from that year by your author:

 (Martin, 1996a, 457)

This citation would lead you to George R.R. Martin’s A Game of Thrones in the references. Once the reader has found the book, she can turn to page 457 to find the original text. For the author's next source from 1996, you'll write 1996b, and so on. 

One Work with Two Authors

For one work with two authors, cite them both each time you mention the source.

(Woodward and Bernstein, 1974)

Three or More Authors

For three or more authors, cite all three the first time, and use first author et al. afterwards. For works with six or more authors, shorten from the first citation onward.

(Dewey, Cheatem, and Howe, 1932)

Place the citations as close to the quotation, paraphrase, or summary as possible. In some instances, you can work all or part of the citation into the main text. When this occurs, you can abbreviate the citation even further:

Martin has a gift for depicting the savagery of war: “quotation goes here” (Game, 457).

Martin’s book A Clash of Kings deftly portrays the savagery of war.

In the second example, since I referred to a full book instead of a particular passage, no page number or year is needed.

Multiple Authors with the Same Last Name

If you have multiple authors with the same last name, include a first initial as well:

Born Standing Up includes a long section explaining the connections between comedians and magicians ( Martin, S., 17-25).

Several Passages from the Same Author in a Row

Citations should be kept low in number and as short as possible. If quoting several passages from the same author in a row, use just the page numbers, since the reader will assume that they come from the same author.

Some sources, such as web sources, will have paragraph numbers instead of page numbers. Use the abbreviation par. to indicate this in your citation. If there are no numbers whatsoever, indicate your position in the text by counting the number of paragraphs:

At the end of a post on Christopher Hitchens, the Boiled Leather blog once again compares the Iraq War to the devastation in the fictional country of Westeros (Collins, 2011, par. 12).

There are other rules for citations in rarer situations. Consult chapter 6 of the APA Publication Manual for more information.