1. Guy Dammann , ‘Harry Potter breaks 400 m in sales’, Guardian 18 June 2008
2. Felicity Wood and Philip Stone , ‘Genre focus: teenage kicks’, Bookseller 22 July 2011
3. David Kleeman , ‘Tracking global kids’ reading habits’, Publishers’ Weekly 25 January 2016, pp. 24–5
4. BfK News – January 1983;Books for Keeps,1983
5. John Ezard , ‘Harry Potter toppled in sales charts’, Guardian 2 June 2006