Schonberger, Richard John, author
N.Y. The Free Press, 1986
Buku Teks
Schonberger, Richard John, author
The Free Press , 1982
Buku Teks
booqs, 2012
Buku Referensi
Peters, Thomas J.
Sang saka gotra, 1985
Buku Teks
Peters, Thomas J
Harper & Row Publisher, 1982
Buku Teks