Liu, James T. C.
Harvard University Press, 1959
Buku Teks
Nasution, Abdul Haris, 1918-2000, author
Seruling Masa, 1967
Buku Teks
Beerling, R.F., author
Pustaka Rakyat, 1957
Buku Teks
Europa Publications Limited, 1970
Buku Referensi
Kennedy, John F.
Harper & Row Pub., 1964
Buku Teks