Guth, Hans P.
Prentice-Hall, 1997
Buku Teks
Ferrell, Wilfred A
Holt, Rinehart and Winston, 1978
Buku Teks
St. Martin's Press, 1978
Buku Teks
Jones, Edward Harrell, 1922-
Macmillan, 1968
Buku Teks
Kearns, Francis E.
Holt, Rinehart and Winston, 1970
Buku Teks