Barghoorn, Frederick C.
Princeton University Press, 1960
Buku Teks
McWhinney, Edward, author
A.W. Sythoff, 1964
Buku Teks
Pentony, Devere E.
Chandler Pub. Co., 1962
Buku Teks
Mosely, Philip E.
Vintage Books, 1960
Buku Teks
Saivetz, Carol R.
Westview Press, 1985
Buku Teks