Wolfe, Gerard R.
McGraw-Hill, 1994
Buku Referensi
Rosenfeld, Paul
University of Illinois, 1961
Buku Teks
Appleton, Julian J.
Practicing Law Institute, 1947
Buku Teks
Rutherfurd, Edward
Ballantine Books Trade Paperbacks, 2010
Buku Teks SO
edited by John W. Wrigth
Penguin Group, 2003
Buku Referensi