Discover GALILEO can be a great tool to discover primary sources on your topic.
For example, searching for "World War II" in Discover GALILEO yields 2,031,996 results.
But with the search of "World War II", Discover GALILEO gives us some interesting primary sources to work with.
As you scroll down, you should see videos from the Associated Press. If these videos were produced during the same time period of World War II, these would count as primary sources. The benefit of searching Discover GALILEO for these video sources is that it also provides a citations in APA, MLA, CMS and Harvard.
This same concept works for articles as well. If you look over to the left of the page, you should see the option to limit to a publication date. If you enter the date of your time period, any articles published during the period of your event would also count as primary sources.