Nussbaum, Arthur
Macmillan, 1958
Buku Teks
Busch, Moel F.
American Heritage Pub. Co., 1972
Buku Teks
Hooker, M. B.
Malaya Law Review, 1967
Buku Teks
Holmes, Oliver Wendell, Jr.
Little, Brown and Company, 1951
Buku Teks
Bogart, Theodore F.
McGraw-Hill, 1992
Buku Teks