Grambs, Jean D.
Holt, Rinehart and Winston, 1964
Buku Teks
Butts, R. Freeman
Beacon Press, 1950
Buku Teks
Severinghaus, Aura E., author
McGraw-Hill , 1953
Buku Teks
Spring, Joel, author
McGraw-Hill, 2008
Buku Teks
Spring, Joel, author
McGraw-Hill, 2004
Buku Teks