edited by Frank Debenham
McGraw-Hill, 1960
Buku Referensi
Stamp, L. Dudley (Laurence Dudley), 1898-1966, author
Penguin Books, 1960
Buku Teks
Fuson, Robert H.
Kendall/Hunt Publishing Co., 1977
Buku Teks
Cipta Hari Bakti, author
Fakultas Ekonomi dan Bisnis Universitas Indonesia, 2013
UI - Skripsi (Membership)
Heintzelman, Oliver H., author
Prentice-Hall, 1960
Buku Teks