1. Azlina, M.K., & Lok, Y.L. (2009). Keberkesanan perisian Geometer's Sketchpad untuk tajuk pembinaan geometri dalam pengajaran dan pembelajaran matematik. Unpublished M. Ed Thesis, Universiti Teknologi Malaysia.
2. Chang, K.E., Sung, Y.T., & Lin, S.Y. (2006). Developing geometry thinking through multimedia learning activities. Computers in Human Behavior, 23(2007), 2212-2229.
3. Clements, D.H. (2004). Perspective on “The child's thought and geometry”. In T. P. Carpenter, J.A.
4. Dossey & J. l. Koehler (Eds.), Classics in Mathematics Education Research (pp. 60-66). Reston: NCTM.
5. Crowley, M.L. (1987). The Van Hiele model of the development of geometric thought. In M.M. Lindquist, Ed., Learning and Teaching Geometry, K-12 (p. 1-16). Reston, VA: National Council of Teachers of Mathematics.