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41A65 Abstract approximation theory (approximation in normed linear spaces and other abstract spaces) (45 articles)

• Beg, Ismat; Abbas, Mujahid: Invariant approximation for fuzzy nonexpansive mappings. (English). Mathematica Bohemica, vol. 136 (2011), issue 1, pp. 51-59
• Duan, Yanzheng; Lin, Bor-Luh: Characterizations of $L^1$-predual spaces by centerable subsets. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 48 (2007), issue 2, pp. 239-243
• Nashine, Hemant Kumar: Best approximation for nonconvex set in $q$-normed space. (English). Archivum Mathematicum, vol. 42 (2006), issue 1, pp. 51-58
• Reich, Simeon; Zaslavski, Alexander J.: Best approximations and porous sets. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 44 (2003), issue 4, pp. 681-689
• Khan, Abdul Rahim; Hussain, Nawab: Characterizations of random approximations. (English). Archivum Mathematicum, vol. 39 (2003), issue 4, pp. 271-275
• Gadjiev, A. D.; Efendiyev, R. O.; Ibikli, E.: On Korovkin type theorem in the space of locally integrable functions. (English). Czechoslovak Mathematical Journal, vol. 53 (2003), issue 1, pp. 45-53
• Veselý, Libor: Chebyshev centers in hyperplanes of $c_0$. (English). Czechoslovak Mathematical Journal, vol. 52 (2002), issue 4, pp. 721-729
• Veselý, Libor: For a dense set of equivalent norms, a non-reflexive Banach space contains a triangle with no Chebyshev center. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 42 (2001), issue 1, pp. 153-158
• Latif, Abdul: A result on best approximation in $p$-normed spaces. (English). Archivum Mathematicum, vol. 37 (2001), issue 1, pp. 71-75
• Karakuş, Yusuf: Best simultaneous $L_p$ approximations. (English). Czechoslovak Mathematical Journal, vol. 48 (1998), issue 3, pp. 457-463
• Kolář, Jan: Porosity and compacta with dense ambiguous loci of metric projections. (English). Acta Universitatis Carolinae. Mathematica et Physica, vol. 39 (1998), issue 1, pp. 119-125
• Cobzaş, S.: Antiproximinal sets in the Banach space $c(X)$. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 38 (1997), issue 2, pp. 247-253
• Zajíček, Luděk: On differentiability properties of Lipschitz functions on a Banach space with a Lipschitz uniformly Gâteaux differentiable bump function. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 38 (1997), issue 2, pp. 329-336
• Kilpeläinen, T.: Smooth approximation in weighted Sobolev spaces. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 38 (1997), issue 1, pp. 29-35
• Baronti, Marco; Fragnelli, Vito; Lewicki, Grzegorz: Extensions of linear operators from hyperplanes of $l^{(n)}_\infty$. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 36 (1995), issue 3, pp. 443-458
• Kasperski, Andrzej: Notes on approximation in the Musielak-Orlicz sequence spaces of multifunctions. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 36 (1995), issue 1, pp. 19-24
• Beckhoff, Ferdinand: Korovkin theory in Banach $^*$-algebras. (English). Mathematica Slovaca, vol. 43 (1993), issue 5, pp. 631-642
• Lewicki, Grzegorz: Strong unicity criterion in some space of operators. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 34 (1993), issue 1, pp. 81-87
• Matoušková, Eva: How small are the sets where the metric projection fails to be continuous. (English). Acta Universitatis Carolinae. Mathematica et Physica, vol. 33 (1992), issue 2, pp. 99-108
• Kilmer, Shelby J.; Kozƚowski, Wojciech M.; Lewicki, Grzegorz: Sigma order continuity and best approximation in $L_\varrho$-spaces. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 32 (1991), issue 2, pp. 241-250
• Delvos, Franz-J.: Approximation by optimal periodic interpolation. (English). Aplikace matematiky, vol. 35 (1990), issue 6, pp. 451-457
• Bogachev, V. I.: Smooth measures, the Malliavin calculus and approximations in infinitedimensional spaces. (English). Acta Universitatis Carolinae. Mathematica et Physica, vol. 31 (1990), issue 2, pp. 9-23
• Nosálová, A.: Abstract analysis of Korovkin approximation theory [Abstract of thesis]. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 30 (1989), issue 1, pp. 194-195
• Narang, T. D.: Characterizations of elements of best approximation in non-Archimedean normed spaces. (English). Archivum Mathematicum, vol. 21 (1985), issue 2, pp. 123-126
• Narang, T. D.: On $f$-best approximation in topological spaces. (English). Archivum Mathematicum, vol. 21 (1985), issue 4, pp. 229-233
• Zajíček, L.: On the Fréchet differentiability of distance functions. (English). In: Frolík, Z. (ed.): Proceedings of the 12th Winter School on Abstract Analysis. Section of Analysis. Circolo Matematico di Palermo, Palermo, 1984. pp. [161]-165
• Dinescu, Gabriela: Weak spectral equivalence and weak spectral convergence. (English). Czechoslovak Mathematical Journal, vol. 34 (1984), issue 2, pp. 203-226
• Zajíček, L.: A generalization of an Ekeland-Lebourg theorem and the differentiability of distance functions. (English). In: Frolík, Zdeněk (ed.): Proceedings of the 11th Winter School on Abstract Analysis. Circolo Matematico di Palermo, Palermo, 1984. pp. [403]-410
• Zajíček, Luděk: On differentiation of metric projections in finite dimensional Banach spaces. (English). Czechoslovak Mathematical Journal, vol. 33 (1983), issue 3, pp. 325-336
• Kopeček, Ivan: A type of continuous projections. (English). Archivum Mathematicum, vol. 19 (1983), issue 4, pp. 209-214
• Burenkov, V. I.: Mollifying operators with variable step and their application to approximation by infinitely differentiable functions. (English). In: John, Oldřich and Kufner, Alois (eds.): Nonlinear Analysis, Function Spaces and Applications, Proceedings of the Spring School held in Písek, 1982. Vol. 2. BSB B. G. Teubner Verlagsgesellschaft, Leipzig, 1982. pp. 5-37
• Bauer, Heinz: Aproximace a abstraktní hranice. (Czech) [Approximation and abstract boundaries]. Pokroky matematiky, fyziky a astronomie, vol. 26 (1981), issue 6, pp. 305-326
• Narang, Tulsi Dass: Best approximation and strict convexity of metric spaces. (English). Archivum Mathematicum, vol. 17 (1981), issue 2, pp. 87-90
• Godini, G.: On certain classes of normed linear spaces. (English). In: Frolík, Zdeněk (ed.): Abstracta. 9th Winter School on Abstract Analysis. Czechoslovak Academy of Sciences, Praha, 1981. pp. 37-41
• Godini, Gliceria: On minimal points. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 21 (1980), issue 3, pp. 407-419
• Stegbuchner, Hans: Zur metrischen Entropie der Lipschitzfunktionen mit vorgegebenen Nullstellen. (German) [On metric entropy of Lipschitz functions with given zeros]. Czechoslovak Mathematical Journal, vol. 28 (1978), issue 2, pp. 286-293
• Zajíček, Luděk: On the points of multivaluedness of metric projections in separable Banach spaces. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 19 (1978), issue 3, pp. 513-523
• Zajíček, L.: On the points of multivaluedness of monotone operators. (English). In: Frolík, Z. (ed.): Abstracta. 6th Winter School on Abstract Analysis. Czechoslovak Academy of Sciences, Praha, 1978. pp. 101-103
• Šmerk, Jiří: The approximation of functions in the sense of Tchebychev. II. (English). Archivum Mathematicum, vol. 12 (1976), issue 3, pp. 117-141
• Milota, Jaroslav: Interpolation in a Banach space. (English). Czechoslovak Mathematical Journal, vol. 26 (1976), issue 1, pp. 84-92
• Šmerk, Jiří: The approximation of functions in the sense of Tchebychev. I. (English). Archivum Mathematicum, vol. 11 (1975), issue 1, pp. 31-51
• Stránská, Carmen: Optimal and Sard approximation. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 16 (1975), issue 3, pp. 567-582
• Přikryl, P.: Universal approximations of certain functionals in Banach spaces. (English). Acta Universitatis Carolinae. Mathematica et Physica, vol. 15 (1974), issue 1, pp. 135-136
• Babuška, Ivo: Approximation by Hill functions. II. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 13 (1972), issue 1, pp. 1-22
• Babuška, Ivo: Approximation by Hill functions. (English). Commentationes Mathematicae Universitatis Carolinae, vol. 11 (1970), issue 4, pp. 787-811