Bernhardt, Robert
West Publishing, 1991
Buku Teks
Thomas, Meryl
Blackstone Press LTD, 2000
Buku Teks
Schlatter, Richard
George Allen & Uwin , 1951
Buku Teks
Macpherson, C.B.
Yayasan LBH Indonesia, 1989
Buku Teks
Haar, Charles M.
Little, Brown, 1977
Buku Teks