1. Albert Einstein, letter to the author 18 September 1952, full text: “Theories avoiding completely the notion of the continuum are, of course possible in principle. But the attempt is not so simple as you seem to believe. The interesting question is if on logical grounds (simplicity) a plausible choice of axioms is possible. Of course, the concept of time (continuum!) could not enter in such a theory.”
2. H. Stevens, (1978) Spec. Sci. Tech 1 99–107
3. H. Stevens, (1980) Spec. Sci. Tech. 3 587–593
4. J.P. Hsu, (1985) Neuvo Ciemento B, 89 14–29