edited by Howard S. Ellis and Henry C. Wallich
Macmillan, 1963
Buku Teks
Wynia, Gary W., author
Cambridge University Press , 1984
Buku Teks
edited by Miguel S. Wionczek
Frederick A. Praeger, 1966
Buku Teks
edited by Eduardo P. Archetti
MacMillan Education, 1987
Buku Teks
Echavarria, Jose Medina, author
New York, N.Y., Unesco
Buku Teks