Burrows, F.
Clarendon Press , 1987
Buku Teks
Ritter, Lennart
Kluwer Law International, 1991
Buku Teks
Medhurst, David
Blackwell Scientific Publications, 1994
Buku Referensi
Paraskos, Ski
Northcote House, 1993
Buku Teks
Cunningham, James P.
Kogan Page, 1973
Buku Teks