edited by Harvey G. Kebschull
Appleton-Century-Crofts , 1968
Buku Teks
Carlson, Fred A., author
Prentice-Hall, 1952
Buku Teks
Slaughter, Frank G
Pocket Books , 1968
Buku Teks
Wilder
Gramedia, 1956
Buku Teks
Audubon, John James, author
Macmillan, 1985
Buku Referensi