Question

For which literary work did Joseph Heller use his military experiences as a primary source?

Answer 1

CATCH- 22 is the literary work in which Joseph Heller use his military experiences as a primary source.
Catch-22 is Joseph Keller most successful novel. After his high school John Keller joined the military and it was his experience during his time there that he used as his primary source in his novel Catch-22. 

Answer 2

It was for Catch-22 that Joseph Heller used his military experiences as a primary source, but it should be noted that he incorporated other several sources as well. 
Hope it helps :}