Commire, Anne, ed. The Writer's Dictionary, 1988-1990. Chicago: St. James Press, 1988. A brief entry on Butterworth includes a career history, current list of publications, and the author's address.

De Montreville, Doris, and Elizabeth D. Crawford, eds. Fourth Book of Junior Authors and Illustrators. New York: H. W. Wilson, 1978. Contains a lengthy sketch by Butterworth that details his boyhood and youth, his travels with his young family, and his thoughts on how he became a writer.

Ethridge, James M., and Barbara Kopala, eds. Contemporary Authors.

Vol. 1. Detroit: Gale Research, 1967.

Includes a short entry on the personal and career history of the author, a list of publications, and a list of hobbies.

Kirkpatrick, D. L., ed. Twentieth-Century Children's Writers. London: Macmillan, 1983. Contains a lengthy entry in which Butterworth summarizes his philosophy of writing, as well as reviews of each of the novels through The Narrow Passage...