<P> The Ain - i - Akbari (Persian: آئینِ اکبری ‎ ‎ ‎) or the "Constitution of Akbar", is a 16th - century, detailed document recording the administration of emperor Akbar's empire, written by his vizier, Abu'l - Fazl ibn Mubarak . It makes the Volume III and the final part of the much larger document, the Akbarnama (Persian: اکبر نامه ‎ ‎ ‎), the Book of Akbar, also by Abul Fazl, and it itself is in three volumes . </P> <P> It is currently housed in the Hazarduari Palace, in West Bengal . </P>

How is ain-i-akbari a useful document for the historians
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