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Franceschi, P. The Doomsday Argument and Hempel's Problem, English translation of a paper initially published in French in the Canadian Journal of Philosophy 29, 139-156, 1999, under the title Comment l'urne de Carter et Leslie se déverse dans celle de Hempel Hempel, C. G. A Purely Syntactical Definition of Confirmation. J. Symb. Logic 8, 122-143, 1943.

Hempel, C. G. "Studies in the Logic of Confirmation (I)" Mind 54, 1-26, 1945.

Hempel, C. G. "Studies in the Logic of Confirmation (II)" Mind 54, 97-121, 1945.

Hempel, C. G. "Studies in the Logic of Confirmation". In Marguerite H. Foster and Michael L. Martin , eds. Probability, Confirmation, and Simplicity''. New York: Odyssey Press, 1966. 145-183.