by Peter Dennis, Jeffrey Grey, Ewan Morris, Robin Prior
Oxford University Press, 1995
Buku Referensi
Moch. Nurhasim
The Ridep Institute, 2005
Buku Teks
Moch. Nurhasim
The Ridep Institute, 2005
Buku Teks
Legarda, Angelita Ganzon De
Bancom Development corporation, 1976
Buku Teks
Agoncillo, Teodora A.
A Mentor Book, 1969
Buku Teks