Institute of Social Science, University of Tokyo,
Majalah, Jurnal, Buletin
Kluwer Academic Publishers,
Majalah, Jurnal, Buletin
Bonner, Thomas Neville
Prentice-Hall, 1960
Buku Teks
Philippines : De La Salle Univesrsity-Manila, 2005,
Majalah, Jurnal, Buletin
Unesco , 1952
Buku Teks