By Zaslavsky
By Marjoram, D.T.E.
By David Bowles, Brian Jefferson, Eddie Mullan, John Rayneau, Mark Rowland
By Gates, Peter
By Helen Forgasz, Ferdinand Rivera
By Bill Atweh, Angela Calabrese Barton, Marcelo C. Borba, Noel Gough, Christine Keitel-Kreidt
By Sal Restivo, Jean Paul Van Bendegem, Roland Fischer
By Martin Gardner
By Fong Ho Kheong, Chelvi Ramakrishnan, Michelle Choo
By Doug Cooper, Michael Clancy
By Sophie Goldie, Susan Whitehouse, Val Hanrahan, Cath Moore, Jean-Paul Muscat
By Collins KS3
By Jamie James
By David Alcorn
By Suman Singha (University of Connecticut, Storrs, CT, USA), Tara Baugher
By Isaacs, Alan, Daintith, John, Martin, Elizabeth
By Carl B. Boyer, Uta C. Merzbach
By SQA
By David Bodanis
By Mark Rowland
By School Mathematics Project
By James M. Brown, Andy Martin, Paul Rigby, Simon Riley
By Natasha Maurits, Branislava Curcic-Blake
By Michael J. Crawley (Imperial College of Science, Technology and Medicine, UK)
By Theoni Pappas
By Rayner, David
By Ian Bloomfield, John Stevens