Griffith, Ernest
Frederick A. Praeger, 1954
Buku Teks
Ferguson, John H., author
McGraw-Hill, 1947
Buku Teks
Ferguson, John H., author
McGraw-Hill, 1965
Buku Teks
Ferguson, John H., author
McGraw-Hill, 1981
Buku Teks
Griffith, Ernest S.
New York University press, 1956
Buku Teks