Shepherd, William G., author
Richard D. Irwin, 1979
Buku Teks
Newman, William H., author
South-Western Publishing Company, 1959
Buku Teks
McKenzie, Richard B., author
McGraw-Hill, 1980
Buku Teks
Johnson, Harry G., author
Praeger , 1968
Buku Teks
Ziegler, Raymond J.
Appleton-Century-Crofts, 1966
Buku Teks