by Prof. Drs. H. A. W. Widjaja $9.00
by Andrias Harefa $7.00
by Walker, Edward L $6.00
by Maesaroh D. Mansur, S.Pd $6.00
by Indra Darmawan, S.E $7.00
by Drs. Bambang S., dkk $9.00