by T. Mulya Lubis, Richard M. Buxbaum $30.00
by Eddy Tano, Dipl. Chem. Eng. $7.00
by Stephen K. Sanderson $12.00
by Drs. H. Lili M. Sadeli, M.Pd & Drs. Maman Ukas $6.00
by Maesaroh D. Mansur, S.Pd $6.00
by Darmadi Durianto, Sugiarto, dkk $7.00