by John F. Saragih $11.00
by Drs. H. Hamdan Aini $9.00
by Prof. Ir. Zoer'ani Djamal Irwan, M.Sc $7.00
by Drs. H. Malayu S.P. Hasibuan $7.00
by Imelda Akmal & Sony Sandjaya $12.00
by Prof. Dr. Ahmad Shalaby $7.00