Geodesic
Constrained extremal problems in $H^2$ and Carleman's formulae
Sbornik. Mathematics, Tome 209 (2018) no. 7, pp. 922-957 Cet article a éte moissonné depuis la source Math-Net.Ru

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We consider the extremal problem of best approximation to some function $f$ in $L^2(I)$, with $I$ a subset of the circle, by the trace of a Hardy function whose modulus is bounded pointwise by some gauge function on the complementary subset. Bibliography: 36 titles.
Keywords: Hardy spaces, extremal problems, approximations in the complex domain, Cauchy problem, inverse boundary problems. 
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L. Baratchart; J. Leblond; F. Seyfert. Constrained extremal problems in $H^2$ and Carleman's formulae. Sbornik. Mathematics, Tome 209 (2018) no. 7, pp. 922-957. http://geodesic.mathdoc.fr/item/SM_2018_209_7_a1/

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