Classical Law: History and Method
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Kamali, Mohammad Hashim. Principles of Islamic Jurisprudence. (Revised edition) Islamic Texts Society.
Masud, Muhammad Khalid, Brinkley Messick, and David S. Powers, "Muftis, Fatwas, and Islamic Legal Interpretation." In Masud, Messick, and Powers, eds. Islamic Legal Interpretation: Muftis and Their Fatwas. Cambridge (MA) and London: Harvard University Press, 1996.