3 posts categorized "Wikipedia"

October 05, 2015

The Myth of the Off-Limits Source

Chelsea blog 2by Chelsea Lee

Proper citation is an important component of any APA Style paper. However, many readers believe certain sources aren’t allowed in APA Style, and they write to us looking for a definitive list of what is off limits. Two of the most common questions are about whether it’s okay to cite websites and whether sources have to have been published within a certain time frame to be cited, such as the last 5 or 10 years.

Do not write sign

Let’s set the record straight: Anything that a reader can retrieve, you can cite as a source in an APA Style reference list. Things the reader can’t retrieve (like a conversation, an unrecorded webinar, or a personal e-mail) can be cited as personal communications (see PM § 6.20). And there are no limits on the age of sources.

But just because you can cite anything as a source doesn’t mean you should. Rather, APA recommends that sources be reliable, primary accounts that represent the most up-to-date information wherever possible. Let’s look at each of these aspects in more detail.

Reliable Sources

A reliable source is one you can trust. Two indicators of reliability are the expertise of the author and the vetting standards of the place of publication. For example, an article written by a researcher and published in a peer-reviewed journal is likely to contain reliable information and thus would make a good source. On the other hand, a random website written by an unknown person, for example, is less likely to be reliable, and thus we would not recommend you cite this source unless you have a good reason (e.g., to talk about the source’s unreliability) or you verify the information yourself using other reliable sources.

However, the mere fact that information is published online is not reason to dismiss it as unreliable. Many scientific, medical, and governmental organizations—such as the Centers for Disease Control and Prevention (CDC), National Institutes of Health, U.S. Census Bureau, and even the APA—publish reliable information on their websites and social media sites. Scientists and research organizations might publish blogs or YouTube videos that are worth citing. Evaluate each source on its own merits for reliability when determining whether to cite it in a paper.

Primary Sources

A primary source presents information gathered firsthand, such as the results of an experiment or data from a survey. Secondary sources present information secondhand—an example would be a textbook summary of a topic or a Wikipedia article. APA recommends citing primary sources whenever possible, because this allows you to verify the accuracy and completeness of the information yourself rather than rely on someone else to do this for you. Secondary sources can be reliable, but it is a best practice of scholarly writing to investigate for yourself if you can. See here and here for more information on primary and secondary sources.

Up-to-Date Sources

APA recommends that you use the most up-to-date research you can find on your topic. However, the meaning of up-to-date will vary depending on the field. Some fields develop faster than others, and even within a field, some information will remain relevant for a long time, whereas other information will become outdated. For example, foundational works may be quite old but still worth citing when you are establishing the context for your own work. There is no year-related cutoff where sources must be published within the past x number of years to be used in a paper. Each source must be evaluated on a case-by-case basis to determine whether the information in it is timely and relevant.

If you have further questions about choosing sources for an APA Style paper, leave a comment below. 

August 21, 2014

When to Include Retrieval Dates for Online Sources

David Becker

By David Becker

We’ve all had that experience when a dog or a child walks up to you holding something dangerous, disgusting, or some other d-word that you absolutely do not want in the house. What’s the one question we’ve all asked in that situation? “Where did you get that?” If it’s something particularly strange, we might also ask, “What in the world is that?” But rarely do we ask, “When did you get that?” We don’t care. We know it’s in the room now. We just want it to go back where it came from.

Dog Doing Research

APA Style generally asks the same thing: “What are you citing, and where did you get it?” We also ask, “Who created it, and when?” But we usually don’t ask, “When did you consult that source?” One exception to this rule would be for material that is subject to frequent change, such as Wikipedia entries. Because this information is designed to be constantly updated, it’s important to let readers know when you retrieved it.

So the next time you ask your dog to fetch sources for your research paper, make sure he tells you what they are, where he got them, who created them, and when they were created. You probably won’t need to ask when he got them, unless he’s a lazy dog who does all his research in Wikipedia. And if he comes back with a stick, don’t cite that.

October 14, 2009

How to Cite Wikipedia in APA Style


by Timothy McAdoo

First things first. Is it a good idea to cite Wikipedia in your research paper? Generally speaking, no. In fact, if you’re writing a paper as a class assignment, your teacher may specifically prohibit citing Wikipedia. Scholarly papers should generally rely on peer-reviewed and other scholarly work vetted by experts in the field.

Does this mean Wikipedia contains bad information? Not at all. It is a great way to get an overview of a topic that might be new to you. And, because many Wikipedia entries contain thorough citations, they can be good starting points to find the original source materials you do want to use. Don’t quote or paraphrase from the Wikipedia entry in your paper, but check the entry’s Reference section to find links to more authoritative sources. And be sure to find and read these sources to verify the facts, figures, and points of view they present.

But, of course, there are times when citing a Wikipedia entry itself is appropriate. For example, let’s say you are writing a paper on how social media and crowdsourcing influence definitions of common psychology terms. Wikipedia would be one excellent source for this topic!

Example 30 (“Entry in an online reference work, no author or editor”) from p. 205 of the Publication Manual can be used for Wikipedia or other wikis. The following example is for the Wikipedia entry on “psychology.” Note that the retrieval date is needed in this case because, as true for any wiki entry, the source material may change over time.

Psychology. (n.d.). In Wikipedia. Retrieved October 14, 2009, from

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