Blodgett, Ralp H., author
Macmillan, 1949
Buku Teks
Loucks, William N., author
Harper and Row, 1965
Buku Teks
Gregory, Paul R., author
Houghton Mifflin , 1992
Buku Teks
Gregory, Paul R., author
Hougton Mifflin, 1985
Buku Teks
Halm, George N., author
Feffer and Simons, 1971
Buku Teks