Coon, Carleton S., author
Henry Holt, 1948
Buku Teks
edited by Bernard J. SIegel
Stanford University Press , 1970
Buku Teks
Greenwood, Susan, author
Berg, 2000
Buku Teks
Hoebel, E. Adamson, author
McGraw-Hill, 1966
Buku Teks
Oliver, Chad
Harper & Row , 1981
Buku Teks