1. Birkhoff, G., and Von Neumann, J. (1936). The logic of quantum mechanics,Annals of Mathematics,37, 823.
2. Braithwaite, R. B. (1953).Scientific Explanation, Cambridge University Press, Cambridge.
3. Braithwaite, R. B. (1960). Models in empirical science, inProceedings of the Congress of the International Union for the Logic, Methodology and Philosophy of Science, E. Nagelet al., eds., Stanford.
4. Carnap, R. (1956). The methodological character of theoretical concepts, inMinnesota Studies in the Philosophy of Science, Vol. 1, H. Feigl, M. Scriven, and G. Maxwell, eds., University of Minneapolis Press, Minneapolis, Minnesota.
5. Carnap, R. (1958).Introduction to Symbolic Logic and Its Applications, Dover, New York.