Isaac Asimov (book title)
Hassler, Donald M. Isaac Asimov. Mercer Island, WA: Starmont, 1991.
Short book, but book-length study by an important critic, including much on the Foundation and Robot series up to I.A.'s Foundation and Earth. Rev. Arthur O. Lewis, SFRA Newsletter #192 (Nov. 1991): 52-53, our source for our citation.