Plucknett, Theodore F. T.
Little, Brown and Company, 1956
Buku Teks
Nussbaum, Arthur, author
Macmillan, 1958
Buku Teks
Busch, Moel F.
American Heritage Pub. Co., 1972
Buku Teks
Hooker, M. B., author
Malaya Law Review, 1967
Buku Teks
Holmes, Oliver Wendell, Jr.
Little, Brown and Company, 1951
Buku Teks