Yerushalmy, M., Katriel, H. & Shternberg, B. (2002/4)  VisualMath: Function. Interactive Mathematics Text. (in Hebrew (2002) and English (2004))  Published by CET:  The Centre of Educational Technology, Ramat-Aviv. www.cet.ac.il/math/function/english, www.cet.ac.il/math/function

Schwartz, J.L., Yerushalmy, M. & Wilson, B. (eds.) (1993) The Geometric Supposer: What is it a case of? Lawrence  Erlbaum Inc., NJ.