By Reader's Digest
By Doug Lennox
By Celador
By Ben Crystal, Adam Russ, Ed McLachlan
By Johnny Ball
By Whitaker, Brian
By BBC
By Anon
By Gifford, Clive
By Pokémon
By Symons, Mitchell
By Tibballs, Geoff
By Strogatz, Steven
By Shenkman, Richard
By DK
By Hensman, Jim
By Rhodes, Chloe
By Clegg, Brian
By National Geographic Kids Magazine, National Geographic Kids
By Standage, Tom
By Ayto, John
By Winn, Christopher
By Martin Cloake, Adam Powley
By Cooke, Ed
By Campbell, T.
By Steve Tribe
By N.E.Thing Enterprises
By Kurtti, Jeff
By Brooke-Taylor, Tim, Cryer, Barry, Garden, Graeme
By The Diagram Group