APA (7th ed.) Citation

Hammond, A. L. (1998). Which world?: Scenarios for the 21st Century. Island Press.

Chicago Style (17th ed.) Citation

Hammond, Allen L. Which World?: Scenarios for the 21st Century. Washington, DC: Island Press, 1998.

MLA (8th ed.) Citation

Hammond, Allen L. Which World?: Scenarios for the 21st Century. Island Press, 1998.