Bloomsbury accepted the book, paying Rowling a £2,500 advance,[17] and Cunningham sent proof copies to carefully chosen authors, critics and booksellers in order to obtain comments that could be quoted when the book was launched.[15] He was less concerned about the book's length than about its author's name, since the title sounded like a boys' book to him, and he believed boys preferred books by male authors. Rowling therefore adopted the nom de plume J.K. Rowling just before publication.[15] In June 1997, Bloomsbury published Philosopher's Stone with an initial print-run of 500 copies in hardback, three hundred of which were distributed to libraries.[18] Her original name, "Joanne Rowling", can be found in small print on the copyright page of this first British edition. (The 1998 first American edition would remove reference to "Joanne" completely.)[19] The short initial print run was standard for first novels, and Cunningham hoped booksellers would read the book and recommend it to customers.[15] Examples from this initial print run have become quite valuable, selling for as much as US$33,460 in a 2007 Heritage Auction.[20]