by Dr. H. Abuddin Nata, MA $7.00
by Wahjosumidjo $13.00
by Ir. M. Iqbal Hasan $12.00
by Muhammad Teguh $7.00
by Prof. Dr. Sondang P. Siagian, M.P.A $11.00
by Dr. Juraid Abdul Latief, M.Hum $7.00