1. Aiken, H. H., & the Staff of the Computation Laboratory at Harvard University. (1951). Synthesis of electronic computing and control circuits. Cambridge: Harvard University Press.
2. What some concepts might not be;Armstrong;Cognition,1983
3. An investigation of the laws of thought on which are founded the mathematical theories of logic and probabilities;Boole,1854
4. Knowing and using concepts;Bourne;Psychological Review,1970
5. Concept learning as a function of the conceptual rule and the availability of positive and negative instances;Bourne;Journal of Experimental Psychology,1969