by Aziz Alimul $9.00
by Raldi Artono $18.00
by Ir. Suharto $7.00
by Eddy Tano, Dipl. Chem. Eng. $7.00
by Thompson Susa $12.00
by Ir. Abbas Siregar Djarijah & Ir. Harsono Puspowardoyo $6.00