By Derek Farmer
By David Pace
By Kevin Houston (University of Leeds)
By M. R. Heylings
By Ewart Smith
By R. Howat
By Holt, Michael
By CGP Books
By Ann Montague-Smith
By Gardner, Kay
By Ruth Merttens, Ba, Med, Dave Kirkby
By Tony and Liz Fleet, Tony Fleet, Liz Fleet
By Scottish Primary Mathematics Group
By Joe Santaniello
By Snape, George, Hall, Marguerite, Heslop, Nigel, Williams, James, Brodie, David
By Fennell, Anne
By School Mathematics Project
By Robert Lomax
By Schofield & Sims, Anne Forster, Paul Martin, Ann Montague-Smith