by Dr. Purnawan Junadi, Ph.D $7.00
by Sumitro Djojohadikusumah $31.00
by Drs. G. Kartasapoetra $12.00
by Iwan Yusi, S.Pd $7.00
by Darmadi D., dkk $7.00
by Ir. Irianto Aritonang $6.00