Informatics and mathematics in secondary schools, impacts and relationships : proceedings of the IFIP TC-3 Working Conference on Informatics and Mathematics in Secondary Schools, Impact and Relationship - Johnson, D. C. (David Carlton), 1936-; Tinsley, J. D. (John David), 1938- (North-Holland Pub. Co., ; sole distributors for the U.S.A. and Canada Elsevier-North-Holland, 1978)