Brian W. Aldiss, with David Wingrove, in Trillion Year Spree: The History of Science Fiction, Gollancz, 1986.

Thomas D. Clareson, Understanding Contemporary American Science Fiction. The Formative Period, 1926-1970, University of South Carolina Press, 1990, pp. 231-33.

Eliot Fremont-Smith, 'The Message and the Maze," in New York Times, March 7, 1966, p. 25.

Mark R. Hillegas, "Other Worlds to Conquer," in Saturday Review, Vol. 49, March 26,1966, pp. 33-4.

"Making up a Mind" (review of Flowers for Algernon), in Times Literary Supplement, No. 3360, July 21,1966, P 629 Robert Scholes, "Structural Fabulation," in his Structural Fabulation' An Essay on Fiction of the Future, University of Notre Dame Press, 1975, pp. 45-76.