Abbaspour-Fard, Mohammad Hossein, Sayed Ali Hoseini, Mohammad Hossein Aghkhani, and Ahmad Sharifi. 2014. “The Behavior of Tillage Tools With Acute and Obtuse Lift Angles”. Spanish Journal of Agricultural Research 12 (1), 44-51. https://doi.org/10.5424/sjar/2014121-4437.