by WK $12.00
by Ir. Hieronymus Budi Santoso $5.00
by Eddy Tano, Dipl. Chem. Eng. $7.00
by Aziz Alimul $7.00
by Syaifuddin $12.00
by Nursalam $7.00
by Drs. Djalinus Syah dan Dra. Azimar Enong $9.00