APA (7th ed.) Citation

Barclay, F. L. (1912). Through the Postern gate: A romance in seven days. The Knickerbocker Press.

Chicago Style (17th ed.) Citation

Barclay, Florence L. Through the Postern Gate: A Romance in Seven Days. New York: The Knickerbocker Press, 1912.

MLA (8th ed.) Citation

Barclay, Florence L. Through the Postern Gate: A Romance in Seven Days. The Knickerbocker Press, 1912.