Trích dẫn APA

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

Trích dẫn kiểu Chicago

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

Trích dẫn MLA

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

Cảnh báo: Các trích dẫn này có thể không phải lúc nào cũng chính xác 100%.