"Secondary sources" refers to reviews, criticism, and explications of your chosen author's work. Remember, these secondary sources are not written by your thinker, but rather by other people about your thinker's works.
While most of your secondary sources should be books, book chapters, or scholarly articles or essays, some may be from journals from the popular press, for example, from The Atlantic, the New Yorker, or magazines of literary criticism.
Start with these six top resources listed below: