Goshu และ Mesfin Tafesse. (2007) The optimum design parameters for a rotary blade power tiller under unsaturated sandy clay loam condition /. Kasetsart University,:ม.ป.ท.Goshu และ Mesfin Tafesse. 2007. The optimum design parameters for a rotary blade power tiller under unsaturated sandy clay loam condition /. ม.ป.ท.:Kasetsart University,;Goshu และ Mesfin Tafesse. The optimum design parameters for a rotary blade power tiller under unsaturated sandy clay loam condition /. ม.ป.ท.:Kasetsart University, 2007. Print.