Durgnat, Raymond. The Strange Case of Alfred Hitchcock. London: Faber and Faber, 1974. (Durgnat explores the audience’s reaction to the character of Norman, the sensitive and charming victim of his "mother’s" control.)
Findley, Janice. "Peeping Tom -1960." Film Comment, May/June 1990. (Findley similarly psychoanalyzes the audience’s reaction to Mark (the peeping tom) and concludes that the villain is really his father.)
Prawer, S. S. Caligari’s Children. Oxford: Oxford University Press, 1980. (Prawer provides an excellent look at the two killers and how they are presented on screen.)
Rebello, Stephen. Alfred Hitchcock and the Making of Psycho. New York: Dembner Books, 1990; and Wiater, Stanley. Dark Visions: Conversations with the Masters of the Horror Film. New York: Avon Books, 1992 (Both provide interviews with Psycho’s screenwriter, Rebello, who details his modifications of the Norman character and the plot from Robert Bloch’s original story.)
Thomson, David, "Mark of the Red Death," Sight and Sound. 49.4, Autumn 1980. (Thompson explores Peeping Tom and its significance in depth.)