Eckholm, E. P. (1978). Disappearing species: The social challenge. Worldwatch Institute.
Citación estilo ChicagoEckholm, Erik P. Disappearing Species: The Social Challenge. [Washington]: Worldwatch Institute, 1978.
Cita MLAEckholm, Erik P. Disappearing Species: The Social Challenge. Worldwatch Institute, 1978.
Warning: These citations may not always be 100% accurate.