Artikel Jurnal
Nila Widowati
1998
UI - Skripsi (Membership)
Wolters, Oliver William
Institute of Southeast Asian Studies , 1996
Buku Teks
Fakultas Psikologi Universitas Indonesia, 2003
UI - Skripsi (Membership)
Parmelee, Maurice
Philosiphical Library, 1960
Buku Teks