Kurtz, David L., author
Professional selling / David L. Kurtz, H. Robert Dodge, Jay E. Klompmaker
Business Publications, Inc., 1982
 Buku Teks
Johnson, Lewis K., author
Sales and marketing management : text and cases
Allyn and Bacon, 1957
 Buku Teks
Dodge, H Robert
Field soles management: text and cases
, Texas Businnes Publicatins , 1973
 Buku Teks
Baker, Robert H.
Astronomy / Robert H. Baker
D. Van Nostrand, 1964
 Buku Teks
Murphy, Robert F., author
Robert H. Lowie
Columbia University Press, 1972
 Buku Teks