Can anyone find *credible primary scholary resources* in relation to the topic New England Patriots vs. Wells Report (deflategate) for my persuasive essay ? A primary source is a document, speech, or other piece of evidence that was created during the period of study. Examples of primary sources include: autobiographies, letters, diary entries, photographs, public records, poetry, news film footage, and speeches. What is a secondary source? A secondary source provides interpretation and analysis of primary sources. Examples of secondary sources include: textbooks, encyclopedias, databases, and literary analyses or critique.