by Doli D. Siregar $48.00
by Dergibson Siagian & Sugiarto $13.00
by Harry Simons $13.00
by Drs. Husein Umar, S.E., M.M., MBA $9.00
by Prof. Dr. J. Winardi, SE $9.00
by PROF. SHOBAH ALI AL-BAYATI $6.00
by Abdul Baqir Zein $6.00
by Susi Soeman & Hein Steinhauer $48.00