Stewart H. Benedict, "Agatha Christie and Murder Most Unsportsmanlike," in Claremont Quarterly, Vol. 9, No. 2, Winter, 1962, pp. 37-42.

David Grossvogel, Death Deferred: The Long Life, Splendid Afterlife, and Mysterious Workings of Agatha Christie, Johns Hopkins University Press, 1979.

Marty S. Knepper, "Agatha Christie-Feminist," in The Armchair Detective, Vol. 16, No. 4, Winter, 1983, pp. 398-406.

Anthony Lejeune, review in Spectator, September 19, 1970.

Max Lowenthal, obituary in New York Times, January 13, 1976, p. 1.

Ralph Partridge, review in New Statesman, November 18, 1939.

Julian Symons, Mortal Consequences: A History-From the Detective Story to the Crime Novel, Harper, 1972.

Robin W. Winks, British Writers, Supplement 2, Scribner's, 1992, pp. 123-37.