by Ir. Abbas Siregar Djarijah & Ir. Harsono Puspowardoyo $6.00
by Ir. Budi Samadi $0.00
by Drh. Nabari Tarigan, MSc $6.00
by Ir. Sudadi Martodireso & Ir. Widada Agus Suryanto, MM $5.00
by Ir. Mul Muyani Sutedjo $7.00
by H. Rahmat Rukmana & Indra Mukti Harahap $5.00