@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/} }