منصور أ. إ. (2008) “Mansour, Ahmad Ibrahim. ‘A Study in the Methodology of Economic Efficiency: ʿUmrān and Khaldūnian Reason as a Model,’ Year 13, Issue 51 (Winter 1429 AH/ 2008 CE), Pp. 263 -284”., Al-Fikr al-islāmī al-muʿāṣir (previously Islamiyat al-Ma’rifah), 13(51), pp. 263–284. doi: 10.35632/citj.v13i51.1223.