'Paper given at the March 1974 Meeting of the Psychology of Mathematics Education Workshop at the Centre for Science Education, Chelsea College, University of London' - note.
Some research studies of the Centre de Recherches en Psychomathématique, Université de Sherbrooke, 1970-73 by John David Williams. ISBN 0904777014. Published by Shell Mathematics Unit, Centre for Science Education, Chelsea College, University of London in 1974. Publication and catalogue information, links to buy online and reader comments.