by Drs. Ec. Alex. S. Nitisemito dan Drs. M. Umar Burham. M.S $6.00
by Drs. H. Malayu S.P. Hasibuan $11.00
by $12.00
by Isjoni $8.00
by Drs. Hasbullah $6.00
by Drs. Daryanto $7.00