- Culkin, John M. “A Schoolman’s Guide to Marshall McLuhan.” The Saturday Review, 18 Mar. 1967, p. 70.
- Commonly attributed to McLuhan, but written by Culkin, Most likely based on an idea originating from McLuhan. More here.
- Marshall McLuhan (1911–1980), Wikipedia
- John M. Culkin, Jr. (1928–1993), Wikipedia