As shown in the image below, a primary source is one that has undergone scientific study or experiment. It is original research that has been complete by specialists, or experts in the field.
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In the previous tab you were able to see an image of a primary source, a scholarly journal article discussing the health impact of green tea in relation to cancer. In the image below is a secondary source. It was written in a newspaper, "The New York Times" and does not offer scientific study or experiment. It doesn't not contain original research, nor was it written by experts in that field. Rather, as a newspaper article it was written by a journalists.
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The link below takes you to a list of databases limited by subject. What's your topic? Be sure to pick a database that covers your subject area. The descriptions for each database tells you what kind or type of article it houses. Most databases will have a variety of sources - like newspapers and magazine articles (secondary) as well as academic or scholarly journal articles (primary). After searching, you'll see a list of results and options to limit to a specific type of source.
"Tyee Yearbook, 1965." UW Digital Collections., https://digitalcollections.lib.washington.edu/
digital/collection/uwdocs/id/7261 Accessed 1 Apr. 2020.
Image taken from the "Report of the Great Plains Drought Area Committee, 1936"