Edmonds, Richard Louis, author
Routledge , 1994
Buku Teks
Moorad, George
E.P. Duttom, 1949
Buku Teks
Chanlett, Emil T., author
McGraw-Hill, 1979
Buku Teks
United Nations Conference on Human Environment, 1972
Buku Teks
Qi, Wen, author
Foreign Languages Press, 1989
Buku Teks