EPB Publ., 1980
Buku Teks
Starr, Wilmarth H.
American Book Company, 1959
Buku Teks
Fucilla, Joseph G.
Follett Publishing Company, 1964
Buku Referensi
Collier, Leonard Dawson
St. Paul's House Warwick Lane, 1973
Buku Teks
Payne, Stanley G.
W.W. Norton, 1970
Buku Teks