Grossfeld, Bernhard
Clarendon Press , 1990
Buku Teks
Ehrmann, Henry W., author
Prentice-Hall, 1976
Buku Teks
Zweigert, Konrad, author
North-Holland, 1977
Buku Teks
Cruz, Peter de
Kluwer, 1993
Buku Teks
Schlesinger, Rudolf B.
Stevens & Sons , 1960
Buku Klasik