Dragomir, Sever Silvestru On best approximation in the sense of Lumer and applications. (English) Zbl 0718.41037 Riv. Mat. Univ. Parma, IV. Ser. 15, 253-263 (1989). Characterizations of best approximation element, semi-Chebyshevian, proximinal and Chebyshevian subspaces in the sense of Lumer are given. Reviewer: S.K.Rangarajan (Karaikudi) Cited in 1 Document MSC: 41A50 Best approximation, Chebyshev systems Keywords:Chebyshev subspace; proximinal subspace; best approximation element PDF BibTeX XML Cite \textit{S. S. Dragomir}, Riv. Mat. Univ. Parma, IV. Ser. 15, 253--263 (1989; Zbl 0718.41037) OpenURL