Gutiérrez Rodríguez, Francisco, 		González Huerta, Andrés, 		Serrato Cuevas, Rodolfo, AND 		Norman Mondragón, Thomas.
" A Technological-Operational Evaluation of the Multi-plow Tractor J. D. Model 4235, During the Primary Preparation of a Vertisol Soil" <em>CIENCIA ergo-sum</em> [Online], Volume 11 Number 2 (12 March 2015)