American Heritage Publishing Company, 2001
Multimedia
Walters, Margan L
N.Y.Holt,Rinehart and winston,ic, 1966
Buku Teks
Houghton Miffiln, 1981
Buku Referensi
editor, William Morris
Houghton Miffiln, 1976
Buku Referensi
N. A. L. Signet Books,
Buku Referensi