A converse of the theorem of mean approximation in domains with corners
English version (Springer): Ukrainian Mathematical Journal 23 (1971), no. 1, pp 85-91.
Citation Example: Andrashko M. I., Kolesnik L. I. A converse of the theorem of mean approximation in domains with corners // Ukr. Mat. Zh. - 1971. - 23, № 1. - pp. 97–104.
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