APA (7th ed.) Citation

Lewis, C. S. (1961). The Screwtape Letters and Screwtape Proposes. G. Bles.

Chicago Style (17th ed.) Citation

Lewis, C. S. The Screwtape Letters and Screwtape Proposes. London: G. Bles, 1961.

MLA (9th ed.) Citation

Lewis, C. S. The Screwtape Letters and Screwtape Proposes. G. Bles, 1961.

Warning: These citations may not always be 100% accurate.