El Khamlichi, A., K. Sarkar, M. Arouri, and F. Teulon. “Are Islamic Equity Indices More Efficient Than Their Conventional Counterparts? Evidence From Major Global Index Families”. Journal of Applied Business Research (JABR), vol. 30, no. 4, June 2014, pp. 1137-50, doi:10.19030/jabr.v30i4.8660.