By PM Heathcote, RSU Heathcote, PG Online
By M.A. Griffin
By P. M. Heathcote
By Brian Gillinder, Sonia Stuart
By AB, Mojang
By Mojang AB
By Jill Jesson, Graham Peacock
By Ann Weidmann
By Ian Rendell, Julian Mott
By David Walton, Martin T. Williams
By Perfect Papers
By David Waller
By Alison Page, David Waters
By Bob Penrose, Bill Pollard
By David Green, Peter Armstrong, Richard Bridges, The Mathematical Association
By J. Muir
By Louie Stowell, Various
By Kevin Wells, Victoria Allen, Sarah McAtominey, Tony Stephens
By Jim Drake