After being sued by J.K. Rowling, a publisher has agreed to delay its plans to release an encyclopedic reference work on the fictitious world of the Harry Potter novels.

RDR Books Publisher Roger Rapoport said he volunteered to halt typesetting on the planned “Harry Potter Lexicon” until a judge rules on whether the work constitutes a violation of Rowling’s intellectual property rights, or the copyright on her novels held by Warner Bros.