Marris, Robin
Free Press of Glencoe, 1964
Buku Teks
Kim, Chaiho
Addison-Wesley , 1976
Buku Teks
Williamson, Oliver E., editor
Ill Markham Publishing , 1967
Buku Teks
Ramalingam, P.
John Wiley and Sons, 1976
Buku Teks
Palda, Kristian S.
Prentice-Hall, 1969
Buku Teks