Proceedings of ICME-11, Topic Study Group 10 : Research and development in the teaching and learning of number systems and arithmetic : 11 International Congress on Mathematical Education, July 6-13, 2008, Monterrey, Mexico / editors, Dirk de Bock ... [et al.]., 160 - 03 - 01 - LD1017 .C8182 2008 C37, Volume: Archives LD1017 .C8182 2008 C37. Clarion University Archives.

Proceedings of ICME-11, Topic Study Group 10 : Research and development in the teaching and learning of number systems and arithmetic : 11 International Congress on Mathematical Education, July 6-13, 2008, Monterrey, Mexico / editors, Dirk de Bock ... [et al.]., 160 - 03 - 01 - LD1017 .C8182 2008 C37, Volume: Archives LD1017 .C8182 2008 C37. Clarion University Archives. http://as-clarion.klnpa.org/repositories/2/resources/702 Accessed December 20, 2025.