Thompson, Mark P.
Oxford University Press, 2001
Buku Teks
Greenspan, Morris
University of California Press, 1959
Buku Teks
Gellhorn, Ernest
West , 1994
Buku Teks
Dobbyn, John F.
West Publishing, 1989
Buku Teks
Lowe, John S.
West Publishing, 1995
Buku Teks