By M. V. Berry, I. C. Percival, N. O. Weiss
By A. G. Hamilton
By Howard Baxter et. al, Mike Handbury, John Jeskins, Jean Matthews, Howard Baxter, Eddie Wilde
By Gordon, Keith
By Catherine Berry, Sophie Goldie, Brandon Wilshaw, Leonie Turner, Margaret Bland
By Marcus Pivato (Associate Professor, Trent University, Peterborough, Ontario)
By Smital
By Erwin Kreyszig (University of Windsor)
By Timothy Poston, Ian Stewart
By Kolman, Bernard, Denlinger, Charles G.
By John A. Dossey, Albert D. Otto, Lawrence E. Spence, Charles Vanden Eynden
By Mridul Sen, D. S. Malik
By Peter MacBride
By Ali Almossawi
By Bird, John O., May, A. J. C.
By J.E. Szymanski
By Leonard Kazmier
By Author Team, Combined
By Collins GCSE
By Jan Dangerfield, Rose Jewell, Sue Pope, Nick Geere
By John D. Collins, etc.
By School Mathematics Project
By Ian McDonagh, G. Waterworth
By Walker, Peter M.B.