Karlen, Delmar
West, 1972
Buku Teks
Ides, Allan, author
Aspen Law & Business, 2003
Buku Teks
Blume, William Wirt
Prentice-Hall, 1955
Buku Teks
Louisell, David W., author
Foundation Press, 1979
Buku Teks
Hall, Livingston, author
West Publishing, 1965
Buku Teks