Abstract
We prove existence theorems and establish necessary and sufficient conditions and criteria for an extremal element for the problem of the best uniform approximation of a continuous compact-valued mapping by sets of continuous single-valued mappings.
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 57, No. 12, pp. 1601–1618, December, 2005.
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Hudyma, U.V. Best uniform approximation of a continuous compact-valued mapping by sets of continuous single-valued mappings. Ukr Math J 57, 1870–1891 (2005). https://doi.org/10.1007/s11253-006-0036-2
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DOI: https://doi.org/10.1007/s11253-006-0036-2