by $4.00
by A. P. Budiyono Hd. $3.00
by H. Rahmat Rukmana $6.00
by Ir. M. Lies Suprapti $5.00
by Drs. Agus M. Hardjana, M.Sc., Ed $6.00
by Al. Wahjasudibja, Pr. $3.00