APA Edition Citation

Schulzinger, R. D. (1990). American diplomacy in the twentieth century (Ed.2.).

Chicago Edition Citation

Schulzinger, Robert D. American Diplomacy in the Twentieth Century. Ed.2. New York, OUP, 1990.

MLA Edition Citation

Schulzinger, Robert D. American Diplomacy in the Twentieth Century. Ed.2. 1990.