1. Anne Marie Helmenstine. What Is Chemistry? Available at: http://chemistry.about.com/cs/chemistry101/f/bldefinition.htm (accessed on December 27, 2012).
2. Cobern, W.W., Schuster, D., Adams, B., Applegate, B., Skjold, B., Undreiu, A., Cathleen, C.L., Janice, D.G. (2010).Experimental Comparison of Inquiry and Direct Instruction in Science. Research in Science & Technological Education, 28(1), 81-96.
3. Furtak, E.M., Tina, S., Heidi, I. and Briggs, D. (2009). Recent Experimental Studies of Inquiry-Based Teaching: A Meta-Analysis and Review. Paper Presented at the European Association for Research on Learning and Instruction. Amsterdam, Netherlands: Leibniz Institute for Science Education, Kiel, Germany.
4. J. Dillon (2008). A Review of the Research on Practical Work in School. Science.Kings College.
5. Hofstein, A. (2004). The Laboratory in Chemistry Education: Thirty Years of Experience with Developmets, Implementation, and Research. Chemistry Education: Research and Practice. 5(3): 247-264.