Sufian, Fadzlan, and Muhamed-Zulkhibri Abd. Majid. 2007. “Bank Mergers Performance and the Determinants of Singaporean Banks’ Efficiency: An Application of Two-Stage Banking Models”. Gadjah Mada International Journal of Business 9 (1), 19-39. https://jurnal.ugm.ac.id/v3/gamaijb/article/view/14916.