<Li> Jump up ^ Cowell, Alan (18 October 1999). "Harry Potter and the Magic Stock; A Children's Book Series Helps Rejuvenate a British Publisher". The New York Times . Retrieved 16 May 2009 . </Li> <Li> ^ Jump up to: Unsworth, John M. "20th - Century American Bestsellers". UIUC Graduate School of Library and Information Science . Archived from the original on 20 August 2012 . Retrieved 16 May 2009 . </Li> <Li> Jump up ^ Winerip, Michael (14 February 1999). "Children's Books". The New York Times . Retrieved 12 January 2009 . </Li> <Li> Jump up ^ "New York Times Best Seller Number Ones Listing Fiction By Date". Hawes Publications . Retrieved 16 May 2009 . </Li>

Why is it harry potter and the philosopher stone