na INLIS000000000004508 0010-0421000073 Farming systems , research and development guidelines for developing countries W.W Shanner W.R Schmehl Boulder, Colorado Westview Press 1982 xviii, 414 p. : ill ; 28 cm 631.58 631.58 SISTEM USAHATANI - NEGARA BERKEMBANG NEGARA BERKEMBANG SISTEM USAHATANI. 1823 1823 1823