Vincent, Andrew
Basil Blackwell, 1987
Buku Teks
Kelsen, Hans
The Lawbook Exchange, 1993
Buku Teks
Ingram, Jefferson L.
Pearson/Prentice Hall, 2005
Buku Teks
Harvard Business School Press, 1991
Buku Teks
Dodd, Walter Fairleigh, 1880-1960
Century, 1923
Buku Teks