Conviser, Richard J., author
HBJ, 1990
Buku Teks
Universitas Indonesia, 1997
UI - Skripsi (Membership)
Bradgate, Robert, author
Butterworth, 1991
Buku Teks
Adams, Kristen David, author
St. Paul, MN : West Group, 2010
Buku Teks
Macintryre, Ewan, author
Blackstone Press, 1998
Buku Referensi