APA (7th ed.) Citation

Ferm, V. (1948). Religion in the twentieth century. Philosophical Library.

Chicago Style (17th ed.) Citation

Ferm, Vergilius. Religion in the Twentieth Century. New York: Philosophical Library, 1948.

MLA (9th ed.) Citation

Ferm, Vergilius. Religion in the Twentieth Century. Philosophical Library, 1948.