by Drs. Nanang Gojali, M.Ag $7.00
by Hasan Shadily, M.A $12.00
by Dr. Sofyan Syafri Harahap, M.S,Ac $11.00
by Hill, Terry $6.00
by Prof. Dr. J. Winardi, SE $11.00
by Stephen K. Sanderson $12.00