1. American Association for the Advancement of Science. (1993). Benchmarks for science literacy. Project 2061. New York: Oxford University Press.
2. A nation at risk. (1983). Report of the U.S. Department of Education's National Commission on Excellence in Education. Washington, DC: U.S. Department of Education. Retrieved June 1, 2002, from http://www.ncrel.org/sdrs/areas/issues/content/cntareas/science/sc3risk.htm
3. Design of virtual environments for the comprehension of planetary phenomena based on students' ideas
4. Concentration analysis: A quantitative assessment of student states
5. Children's understanding of familiar astronomical events