@article{RM_1963_18_5_a3,
     author = {V. M. Tikhomirov},
     title = {Kolmogorov's work on $\varepsilon$-entropy of functional classes
},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {51--87},
     publisher = {mathdoc},
     volume = {18},
     number = {5},
     year = {1963},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_1963_18_5_a3/}
}