APA (7th ed.) Citation

Spengler, O. (1939). The decline of the west. Knopf.

Chicago Style (17th ed.) Citation

Spengler, Oswald. The Decline of the West. New York: Knopf, 1939.

MLA (9th ed.) Citation

Spengler, Oswald. The Decline of the West. Knopf, 1939.

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