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2. and The Growth of Logical Thinking from Childhood to Adolescence, Basic Books, Inc., 1958, pp. 251, 277.
3. Handbook of Chemistry, Sandusky, Ohio: Handbook Publishers, Inc., 6th ed., 1946.
4. , and College Chemistry, A Systematic Approach, New York: The Macmillan Co., 1961, pp. 215, 224–225.
5. (tape Magic Mountain Series) Evanston High School Critical Thinking Experiment, 1960.