by $3.00
by W. Mangoendidjojo $9.00
by Ir. H. Rahmat Rukmana - Hj. Yuyun Yuniarsih, BSc. $5.00
by Haryoto $5.00
by Ir. M. Lies Suprapti $6.00
by Henri J. M. Nouwen $4.00
by Dr. Ir. Muhammad Rasyaf, MS $7.00