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@article{MAT_1974_18_1_a8, author = {Per Enflo}, title = {A counterexample to the approximation problem in {Banach} spaces}, journal = {Matematika}, pages = {146--155}, publisher = {mathdoc}, volume = {18}, number = {1}, year = {1974}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MAT_1974_18_1_a8/} }
Per Enflo. A counterexample to the approximation problem in Banach spaces. Matematika, Tome 18 (1974) no. 1, pp. 146-155. http://geodesic.mathdoc.fr/item/MAT_1974_18_1_a8/