Glendon, Mary Ann
West Academic Publishing, 1999
Buku Teks
Zweigert, Konrad
North-Holland, 1977
Buku Teks
Ehrmann, Henry W.
Prentice-Hall, 1976
Buku Teks SO
Schlesinger, Rudolf B.
Stevens & Sons, 1960
Buku Klasik
Cruz, Peter de
Kluwer, 1993
Buku Teks SO