Wynia, Gary W., author
Cambridge University Press , 1984
Buku Teks
Martin, Michael Rheta, author
The Bobbs Merrill, 1968
Buku Referensi
Wilgus, A. Curtis, author
Barner & Noble, 1963
Buku Teks
Williams & Willkins, 1989
Buku Teks
Kendall/Hunt, 1982
Buku Teks