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2. P. Humphreys,Philos. Rev. 94, 557 (1985).
3. P. Milne,Erkenntnis 25, 129 (1986).
4. K. R. Popper,The Logic of Scientific Discovery (Hutchinson, London, 1959), English translation ofLogik der Forschung (Julius Springer, Vienna, 1934).
5. K. R. Popper,Realism and the Aim of Science [The Postscript to The Logic of Scientific Discovery, Vol. I] (Hutchinson, London, and Rowman & Littlefield, Totowa, 1983).