Majid, M. Shabri Abd., and Hartomi Maulana. 2012. “A Comparative Analysis of the Productivity of Islamic and Conventional Mutual Funds in Indonesia: Data Envelopment Analysis (DEA) and General Least Square (GLS) Approaches”. Gadjah Mada International Journal of Business 14 (2), 183 - 208. https://journal.ugm.ac.id/v3/gamaijb/article/view/15367.