by Ir. Doli Siregar, M.Sc., FRICS., SVC $11.00
by Drs. Muchdarsyah Sinungan $7.00
by Muana Nanga $13.00
by Prof. DR. Made Pidarta $11.00
by $9.00
by Prof. Dr. Nur Nasry Noor, M.P.H $6.00