1. Bednarz, N., Kieran, C., and Lee, L. (1996). Approaches to Algebra: Perspectives for Research and Teaching, Kluwer.
2. Kilpatrick, J., Swafford, J., and Findell, B. (2001). Adding It Up: Helping Children Learn Mathematics, The National Academies Press.
3. Kieran, C. (2020). Encyclopedia of Mathematics Education, Springer.
4. An analysis of errors made in the solution of simple linear equations;Hall;Philos. Math. Educ.,2002
5. Grouws, S.D.A. (1992). Handbook of Research on Mathematics Teaching and Learning, National Council of Teachers of Mathematics.