by Dr. Ir. Muhammad Rasyaf, MS $11.00
by Drs. Robinson Tarigan, M.R.P $11.00
by Ir. Hatta Sunanta, B.Sc., MS $5.00
by drh. N. Tarigan, MSc $6.00
by Ir. Suprio Guntoro $5.00
by Bambang Agus Murtidjo $6.00