Q. F. Dar, A. Y. Hyo, G. F. Dar, S. A. Bhat, A. M. Tali, and Y. H. Bhat, “Fuzzy Data envelopment Analysis with SBM using ?-level Fuzzy Approach”, Pak.j.stat.oper.res., vol. 15, no. 2, pp. 481-501, Jun. 2019.