Maxwell, Kenneth E.
Dickenson , 1973
Buku Teks
Ashby, Eric
Stanford University Press, 1978
Buku Teks
Watson, Richard A.
Harcourt, Brace and World, 1969
Buku Teks
edited by Gwen Bell
Hawaii University Press, 1976
Buku Teks
Smidak, E.F.
Avenira Foundation for Research of Human Society, 1996
Buku Teks