Fadavi, R., N. S. Naiemeh Samavatean, A. . Keyhani, and S. S. . Mohtasebi. “An Analysis of Improving Energy Use With Data Envelopment Analysis in Apple Orchard”. Asian Journal of Agriculture and Rural Development, vol. 2, no. 2, June 2012, pp. 277-86, http://archive.aessweb.com/index.php/5005/article/view/559.