APA
Lewis C. S., . (1944). The screwtape letters. New York: Macmillan.
Chicago
Lewis C S, . 1944. The screwtape letters. New York: Macmillan.
Harvard
Lewis C. S., . (1944). The screwtape letters. New York: Macmillan.
MLA
Lewis C S, . The screwtape letters. New York: Macmillan. 1944.
