Andersen, Dines
Copenhagen: Gyldendalske Boghandel, 1907
Buku Teks
American Psychiatric Press, 1984
Buku Referensi
Redden, Kenneth R.
The Michie Company, 1980
Buku Referensi
New York Institute of Finance, 1988
Buku Teks
Florentinus Gregorius Winarno
M-BRIO Press, 2002
Buku Referensi