D. Carraher, und D. Earnest. Proceedings of the 2003 Joint Meeting of PME and PMNA (PME27 and PME-NA25), 2, Seite 173--180. 1776 University Av., Honolulu, HI 96822, International Group for the Psychology of Mathematics Education, College of Education, University of Hawai'i, (Juli 2003)
D. Carraher, A. Schliemann, und B. Brizuela. Proceedings of the XXV Conference of the International Group for the Psychology of Mathematics Education, (2001)