Reinke, William A., author
The John Hopkins University Press , 1972
Buku Teks
Spiegel, Allen D., author
Ablex Publishing Corporation, 1991
Buku Referensi
Bradshaw, Peter L., author
Sage, 2004
Buku Teks
Blum, Henrik L.
Human Science Press, 1981
Buku Teks
Nutt, Paul C.
John Wiley & Sons, 1984
Buku Teks