First edition Harry Potter book with JK Rowling's notes goes under the hammer

If you want to know what JK Rowling thought about the book that introduced Harry Potter to the world, now is your chance.

A first edition of "Harry Potter and the Philosopher's Stone" is being auctioned, complete with the author's scribbled note that it 'changed her life for ever'.

It is one of more than 50 books containing notes by their authors, which are up for auction tomorrow at Sotheby's in London.

The sale called "First Editions, Second Thoughts" is raising money for the writers' association English Pen.