Zhang, Rentian. 1992. Efficiency of rice based cropping systems in Chiang Mai Valley. Chiang Mai:Chiang Mai University;
Zhang, Rentian. (1992) Efficiency of rice based cropping systems in Chiang Mai Valley (รายงานผลงานวิจัย). Chiang Mai University:Chiang Mai.
Zhang, Rentian. Efficiency of rice based cropping systems in Chiang Mai Valley. Chiang Mai:Chiang Mai University, 1992.
Zhang, Rentian. (1992) Efficiency of rice based cropping systems in Chiang Mai Valley (รายงานผลงานวิจัย). Chiang Mai University:Chiang Mai.