by Dr. Lijan Poltak Sinambel, M.M., M.Pd., dkk $9.00
by Syahrin Harahap $9.00
by Drs. Surajiyo $9.00
by Dr. Oemar Hamalik $7.00
by Prof. Dr. S. Nasution, M.A. $7.00
by Peter H. Lindert $26.00