Siegel, David D.
Conflicts in a nutshell / by David D. Siegel
West Pub. Co., 1994
Buku Teks SO
Siegel, Eric S.
The Arthur young business plan guide / Eric S. Siegel, Loren A. Schultz, Brian R. Ford; edited by David C. Carney
John Wiley & Sons, 1987
Buku Teks
Walker, Theodore D.
Plan graphics/ Theodore D. Walker, David A Davis
Van Nostrand Reinhol, 1990
Buku Teks SO
The Diplomatic record 1989-1990 / edited by David D. Newsom
Westeriew Press, 1991
Buku Teks SO
Indonesia / by J, D. (John David) Legge
Prentice-Hall, 1980
Buku Teks SO