APA (7th ed.) Citation

Butler, N. M. (1940). Why war?: Essays and addresses on war and peace. Scribner.

Chicago Style (17th ed.) Citation

Butler, Nicholas Murray. Why War?: Essays and Addresses on War and Peace. New York [u.a.]: Scribner, 1940.

MLA (8th ed.) Citation

Butler, Nicholas Murray. Why War?: Essays and Addresses on War and Peace. Scribner, 1940.

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