Samuels, Charles E.
Twayne, 1965
Buku Teks SO
Lorant, Stepan
N.Y,Simon and Schuster, 1950
Buku Teks
Leutenburg, William E
Pustaka Sinar Harapan, 1994
Buku Teks
by Agoes Ariesmunandar, Julian Davison, Bea Bromer and Jacques Durmacay
Archipelago Press, 1998
Buku Referensi
editor Haryati Soebadio
Archipelago Press, 1998
Buku Teks SO