Still, Richard R., author
Prentice-Hall, 1958
Buku Teks
Johnson, Lewis K., author
Allyn and Bacon, 1957
Buku Teks
Dodge, H. Robert
Business Publications, 1973
Buku Teks
Still, Richard R
Prentice Hall International, 1988
Buku Teks
Jones, John G., author
Alexander Hamilton Institute, 1961
Buku Teks