1. EPC (1961). Educational Policies Commission: The Central Purpose of American Education, National Education Association.
2. The nature and development of scientific reasoning: A synthetic view;Int. J. Sci. Math. Educ.,2004
3. EPC (1966). Educational Policies Commission: Education and the Spirit of Science, National Education Association.
4. EURYDICE (2011). Mathematics Education in Europe: Common Challenges and National Policies, Education, Audiovisual and Culture Executive Agency.
5. EURYDICE (2011). Science Education in Europe: National Policies, Practices and Research, Education, Audiovisual and Culture Executive Agency.