"He (Muhammad Ghauri) now possessed Alberuni's India and Burhanuddin's Hidayah, works which were not available to his predecessor invader. Alberuni's enecyclopedic work provided to the Islamic world in the eleventh century all that was militarily advantageous to know about India. Equally important was the Hidayah, the most authentic work on the laws of Islam compiled by Shaikh Burhanuddin Ali in the twelfth century. These and similar works, and the military manuals like the Siyasat Nama and Adab-ul-Harb, made the Ghauris and their successors better equipped for the conquest and governance of non-Muslim India. There need be no doubt that such works were made available, meticulously studied and constantly referred to by scholars attached to the courts of Muslim conquerors and kings."