APA (7th ed.) Citation

Pepper, D., Perkins, J., & Youngs, M. J. (1984). The roots of modern environmentalism. Croom Helm.

Chicago Style (17th ed.) Citation

Pepper, David, John Perkins, and Martyn J. Youngs. The Roots of Modern Environmentalism. London ; Dover, N.H.: Croom Helm, 1984.

MLA (9th ed.) Citation

Pepper, David, et al. The Roots of Modern Environmentalism. Croom Helm, 1984.