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Gottlob Frege, “Sense and Reference,” The Philosophical Review, M. Black (tr.), vol. 57 (1948), pp. 209-230 (on JSTOR at 2181485)

Gottlob Frege, “The Thought: A Logical Inquiry,” A. M. and M. Quinton (trs.), Mind, n.s. vol. 65 (1956), pp. 289-311 (on JSTOR at 2251513)

Bertrand Russell, “On Denoting,” Mind, n.s. vol. 14 (1905), pp. 479-493 (on JSTOR at 2248381)

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