By Jones, Rhodri
By Brookes, H.F., Fraenkel, C.E., C.E. Fraenkel
By Nettle, Gillian, Leach, Julia, Leech
By Hulme-Cross, Benjamin
By Hayes, Ian
By Margaret Mahy, Nick Price
By Nash, Deborah
By Benjamin Hulme-Cross, Hulme-Cross, Benjamin
By Vogel, Arthur Israel, Smith, Peter William George, etc.
By Loves, June, Kennett, David
By Patircia Hammond, Kiki Ketcham-Neumann
By Jones, Michael, Dyke, Kevin
By Scottish Primary Mathematics Group
By Needham, David, Dransfield, Robert
By Various
By Reid, Victor Stafford
By Cowley, Joy
By Ganson, Trevor, etc.
By Tyas, J.G.M., Pannett, Alan
By Martin et al
By Vossen, Gottfried
By Naidoo, Beverley