Ohara, John B.
N,Y. Holt , 1964
Buku Teks
Blyth, Conrad Alexander
Allen & Unwin, 1966
Buku Teks
Larsen, Richard J., author
Macmillan, 1976
Buku Teks
McClave, James T., author
Prentice-Hall, 2000
Buku Teks
McClave, James T., author
Dellen Publishing, 1979
Buku Teks