Roney, Alex.
Kogan Page, 1995
Buku Teks
Burrows, F.
Clarendon Press , 1987
Buku Teks
Ritter, Lennart, author
Kluwer Law International, 1991
Buku Teks
Medhurst, David, author
Blackwell Scientific Publications, 1994
Buku Referensi
Paraskos, Ski, author
Northcote House, 1993
Buku Teks