Παραπομπή APA

Nancy,K Hetzel. (1980). Environmental cooperation among industrialized countries: The role of regional organizations. University Press of America,Inc.

Παραπομπή Chicago Style

Nancy,K Hetzel. Environmental Cooperation Among Industrialized Countries: The Role of Regional Organizations. Washington: University Press of America,Inc, 1980.

Παραπομπή MLA

Nancy,K Hetzel. Environmental Cooperation Among Industrialized Countries: The Role of Regional Organizations. University Press of America,Inc, 1980.