Steen, L. A. (1978). Mathematics today: Twelve informal essays. Springer-Verlag.
Style de citation Chicago (17e éd.)Steen, Lynn Arthur. Mathematics Today: Twelve Informal Essays. New York: Springer-Verlag, 1978.
Style de citation MLA (8e éd.)Steen, Lynn Arthur. Mathematics Today: Twelve Informal Essays. Springer-Verlag, 1978.
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