Pious, Richard M
Basic Books, 1944
Buku Teks
Kemper, Alfred M., author
John Wiley & Sons, 1973
Buku Teks
Jenkins, Jeffrey A. , author
Jones and Bartlett Publishers LLC , 2011
Buku Teks
Casper, Lynne M., author
Sage, 2000
Buku Teks
Hacker, Louis M., author
Columbia University Press, 1947
Buku Teks