Cita APA (7th ed.)

Dixon, J. A., & Sherman, P. B. (1990). Economics of protected areas: A new look at benefits and costs. Island Press.

Cita Chicago (17th ed.)

Dixon, John A., i Paul B. Sherman. Economics of Protected Areas: A New Look at Benefits and Costs. Washington, D.C: Island Press, 1990.

Cita MLA (9th ed.)

Dixon, John A., i Paul B. Sherman. Economics of Protected Areas: A New Look at Benefits and Costs. Island Press, 1990.