One of the main factors that distinguishes scholarly from popular sources is that scholarly sources are peer-reviewed. Peer-reviewed means other scholars in the same field have reviewed the material before it is published. They may suggest revisions or even reject it entirely. Almost every prestigious academic journal is peer-reviewed. There are a number of reasons why peer-reviewed articles are considered superior:

Although the process varies depending on publisher, books published by academic presses such as monographs or edited volumes also undergo a form of peer review.

Some assignments may require that you only use peer reviewed papers as references. Academic search engines such as Google Scholar often provide a filter to only return peer reviewed papers.

Wikipedia is one of the most popular sources of information for the general public, and has many quality articles on a diverse range of topics. The fact that anyone can create or edit articles means that it isn’t regarded as a scholarly source. Another issue is that wikipedia articles are constantly changing. It is generally safe to use wikipedia as an introduction to a subject and as a way to identify primary sources of information, but don’t cite it directly. In other words, Wikipedia is mostly useful for background information and as a pointer to other sources.

It pays to check with your university, but at most universities it is acceptable to use a textbook as a reference for introductory undergraduate courses. Although the textbook may not necessarily incorporate the latest research, and are not typically peer-reviewed in exactly the same way journal articles are, they are still written by experts in the field and nearly always reviewed by other academics. Thus, they are regarded as scholarly enough for some undergraduate assignment purposes. For higher level undergraduate courses, check with your instructor before citing your textbook in an assignment, it could be expected that you will rely exclusively on the primary literature.

Generally, course notes should not be used as a reference. These have not been reviewed in the same way that a journal article, scholarly book, or textbook has. In addition, course notes are often abbreviated and lack the level of detail needed for a written assignment. The person who created the course notes likely just copied them from a textbook anyway which could be referred to instead. In many cases, when academics adopt a particular textbook, the publisher provides them with resources such as slides and other materials to use. It makes more sense to directly reference the sources that the lecturer has used.

The best way to locate scholarly sources is to use an academic search engine (academic research database) like Google Scholar. In many cases, Google Scholar will include not just the author, title, abstract, and other metadata, but also a link to the full article. In some cases the article will be behind a paywall. If so, check if your university has a subscription to that journal, which will allow access through the library website.

Another useful feature of Google Scholar is its cited by feature which indicates how many times a journal article has been cited. For many undergraduate assignments, this is an adequate metric to identify some of the more influential and important articles.

Research databases will be more reliable than a typical search engine in that they only index credible resources. Research databases offer various filtering options such only returning "peer-reviewed" or more recent works. As mentioned earlier, peer-reviewed means the article was scrutinised by subject-matter experts before publication. This increases the accuracy and credibility of the content.

There are many competing search engines, both free and paid, some of which cover all subjects and others which focus on specific areas.

For some assessments, you might need to use sources other than those published in prestigious academic journals. One test for evaluating any source is the TRAAP test. This was created by the Australian National University (ANU) based on an earlier test created by a team at California State University’s Meriam library in 2004 (the so called C.R.A.A.P test) [1].

Currently there is a proliferation of misinformation and disinformation online. Some bad actors are extremely sophisticated at propagating deliberately fake information. Traditional tools like TRAAP may not be adequate for detecting this kind of deception. One study found university students struggled to identify that a story from a satirical news site was not actually real. In addition, students couldn’t determine that a supposedly objective website about minimum wage laws had actually been created by a public relations firm with funding from those opposed to increases in the minimum wage [2].

Methods like TRAAP / CRAAP encourage a deep dive into a given site to assess its credibility, whereas a lateral fact checking approach may be more suitable. This means a site needs to be assessed by looking for information outside the site in order to determine who is behind the site and what agenda may exist [3, 4].

Another approach useful for evaluating web sources is SIFT. This was developed by Mike Caulfield and consists of the following steps [5]:

In academic writing the most common source will be scholarly journals. However, books that are scholarly in nature are also acceptable sources. Textbooks are sometimes an acceptable source, especially for introductory courses. Always check with your lecturer or tutor if in doubt, as sometimes rules can vary from course to course.

Be cautious about using popular sources of information. There is a lot of unreliable and inaccurate information on the web. Any sources need to be checked using tools like SIFT and TRAAP.

[1] S. Blakeslee, “The CRAAP test,” Loex Quarterly, vol. 31, no. 3, p. 4, 2004.

[2] S. Wineburg, J. Breakstone, N. Ziv, and M. Smith, “Educating for misunderstanding: How approaches to teaching digital literacy make students susceptible to scammers, rogues, bad actors, and hate mongers,” Stanford History Education Group Working Paper No. A-21322). Retrieved March, vol. 2, p. 2021, 2020.

[3] J. A. Fielding, “Rethinking CRAAP: Getting students thinking like fact-checkers in evaluating web sources,” College & Research Libraries News, vol. 80, no. 11, p. 620, 2019.

[4] S. Wineburg and S. McGrew, “Lateral reading and the nature of expertise: Reading less and learning more when evaluating digital information,” Teachers College Record, vol. 121, no. 11, pp. 1–40, 2019.

[5] “SIFT (The Four Moves).” https://hapgood.us/2019/06/19/sift-the-four-moves/ .