We do not decide your source types

Here on the APA Style team, we help you cite your sources, but we do not provide guidance on what sources to use. The appropriateness of sources such as retracted sources; encyclopedias (e.g., Oxford Research Encyclopedias), which are secondary sources; non-peer-reviewed textual sources such as newspapers, magazines, and blogs; social media (e.g., TikTok); YouTube; and even AI chats depends on the context of use. Nevertheless, your instructors, editors, institutions, and organizations may have their own guidelines about which source types you can use in your work.

That is, a source might be appropriate in one case but not in another. For example, a professor might say “no Wikipedia” because they want students to use primary sources (i.e., original content) and an encyclopedia like Wikipedia is a secondary source (i.e., content reported in another source). However, they might nonetheless approve of Wikipedia references if the topic of your paper is about how people collaborate online and you use some Wikipedia entries as examples. (Also, most Wikipedia pages include a reference list, so it is possible to use Wikipedia as a starting point to find legitimate primary sources for your work.) Likewise, although you would want to avoid citing a retracted article, if you’re writing a paper about why works are retracted or comparing research from an author’s previously published works to that of their retracted article, you’ll need to cite the retracted article.

Before you use and rely on information from the sources you find, especially those from the internet, it is paramount that you discuss your source types with the individual(s) who will evaluate your work to ensure you are following their or your institution’s directions on the matter. The APA Style team cannot give you permission to use a specific source of information—unless you are officially requesting to use our documents. We can help you with correctly formatting the reference list entries (and in-text citations) for your work.

For general information about references, visit our References page; for specific examples, visit our Reference Examples page; also review this “outdated sources myth” blog post; and if you are studying nursing, visit our Nursing Student References page. You can also find more information about references in Chapters 9 and 10 in the Publication Manual (7th ed.) or in the Concise Guide to APA Style (7th ed.).