APA (7th ed.) Citation

Pen, J., & Preston, T. S. (1980). Modern economics (2nd ed.). Penguin Books.

Chicago Style (17th ed.) Citation

Pen, Jan, and Trevor S. Preston. Modern Economics. 2nd ed. New York: Penguin Books, 1980.

MLA (9th ed.) Citation

Pen, Jan, and Trevor S. Preston. Modern Economics. 2nd ed. Penguin Books, 1980.