APA (7th ed.) Citation

Sarre, P., & Blunden, J. (1995). An Overcrowded World ?: Population, resources and the environment. The Open University.

Chicago Style (17th ed.) Citation

Sarre, Philip, and John Blunden. An Overcrowded World ?: Population, Resources and the Environment. Oxford: The Open University, 1995.

MLA (8th ed.) Citation

Sarre, Philip, and John Blunden. An Overcrowded World ?: Population, Resources and the Environment. The Open University, 1995.