by $16.00
by Prof. Dr. Loekman Soetrisno $6.00
by Al. Wahjasudibja, Pr. $6.00
by Ir. Hieronymus Budi Santoso $5.00
by Ir. L. Widarto & FX. Sudarto C. Ph $5.00
by Ir. H. Rahmat Rukmana $6.00