by AAK (Aksi Agraris Kanisius) $6.00
by Dr. H. Abuddin Nata, MA $6.00
by Ir. H. Rahmat Rukmana, MBA., M.Sc. & Uu Sugandi Saputra, B.Sc $6.00
by Jaih Mubarok $7.00
by Zairin Harahap $9.00
by $7.00