Greenspan, Morris
University of California Press, 1959
Buku Teks
Thompson, Mark P.
Oxford University Press, 2001
Buku Teks
Rose, Francis
Sweet & Maxwell, 1989
Buku Teks
Findley, Roger W.
West Publishing, 1992
Buku Teks
Hamilton, Robert W.
West Publishing, 1996
Buku Teks