APA (7th ed.) Citation

Zehna, P. W., & Johnson, R. L. (1972). Elements of set theory (2. ed.). Allyn and Bacon.

Chicago Style (17th ed.) Citation

Zehna, Peter W., and Robert L. Johnson. Elements of Set Theory. 2. ed. Boston [u.a.]: Allyn and Bacon, 1972.

MLA (9th ed.) Citation

Zehna, Peter W., and Robert L. Johnson. Elements of Set Theory. 2. ed. Allyn and Bacon, 1972.