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2. S. N. Bernstein, ‘Extremal Properties of Polynomials’, ONTI, 1937.
3. J. A. Clarkson, ‘Uniformly Convex Spaces’, Trans. Amer. Math. Soc. 40, 3 (1936) 396–414.
4. N. V. Efimov and S. B. Stečkin, ‘Certain Properties of Chebyshev Sets’, Dokl. Akad. Nauk SSSR 118, (1958) 17–19.
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