Wade, E. C. S. (Emlyn Capel Stewart), author
Longmans Green, 1951
Buku Teks
Schmitt, Carl, author
Duke University Press, 2008
Buku Teks
Kortmann, C.A.J.M., author
Kluwer Law International, 2007
Buku Teks
Landsberg, Brian K., author
Thomson/West, 2007
Buku Teks
Laurel, Jose P., author
Lyceum Press, 1966
Buku Referensi