by Ir. Ari Wijayani Purwanto $11.00
by J. Heinrich Arnold $4.00
by Ir. Sudadi Martodireso & Ir. Widada Agus Suryanto, MM $5.00
by Ir. G. Djatmiko Sudarmo & Ir. S. J. Edy Purnomo $12.00
by Prof. Dr. Winardi $9.00
by Suharso, A.S.P $6.00