Hicks, Herbert G.
Modern business management : a systems and environmental approach
McGraw-Hill Kogakusha, 1974
 Buku Teks
Friedman, Lawrence M., 1930-
American law
W.W. Norton, 1984
 Buku Teks
Kubasek, Nancy K.
Environmental law
Pearson - Prentice Hall, 2005
 Buku Teks SO
Leeson, John D.
Environmental law
Pitman, 1995
 Buku Teks SO
Rodgers, William H.
Environmental law
[Publisher not identified], 1977
 Buku Teks SO