1. Burton, G. (1979). Comfortable with mathematics. The Elementary School Journal, 79(3), 129–135.
2. Cohen, L., Manion, L., & Morrison, K. (2007). Research methods in education. Oxford: Routledge.
3. Cross, D. I. (2009). Alignment, cohesion, and change: Examining mathematics teachers’ belief structures and their influence on instructional practices. Journal of Mathematics Teacher Education, 12(5), 325–346.
4. Di Martino, P. (2016). Attitude. In Attitudes, beliefs, motivation and identity in mathematics education - An overview of the field and future directions (vol. 2, pp. 185–192). Cham: Springer International Publishing.
5. Di Martino, P., & Sabena, C. (2011). Elementary pre-service teachers’ emotions: Shadows from the past to the future. In K. Kislenko (Ed.), Proceedings of MAVI 16 (pp. 89–105). Tallinn: Tallinn University of Applied Sciences.