Ibbot, Anthony Charles
Calif Anthony Charles Ibbot Foundation , 1993
Buku Teks
McMillan, 1962
Buku Referensi
Deem, Bill R.
Reston Publishing, 1980
Buku Teks
American Geogphysical Union, 1966
Buku Teks
Hyman, David N.
Times Mirror/Mosby College, 1986
Buku Teks