by R.W Alley $6.00
by AAK (Aksi Agraris Kanisius) $7.00
by N. Edy Soetanto, BE. $5.00
by Ir. Suprio Guntoro $6.00
by Ir. Hatta Sunanta, B.Sc., MS $7.00
by Christine A. Adams & Roberts J. Butch $6.00