Hale, John R., author
Time-Life International, 1969
Buku Teks
Sypher, Wylie
Doubleday & Company, 1956
Buku Teks
Andrews, Richard, author
Cambridge University Press, 2009
eBooks
Faizul Azhaari Tri Raharjo, author
Fakultas Ilmu Pengetahuan dan Budaya Universitas Indonesia, 2021
UI - Tugas Akhir
Butterfield, Herbert
The Free Press , 1957
Buku Teks