@article{10_21136_AM_1979_103824,
     author = {Pr\'ager, Milan},
     title = {Universally optimal approximation of functionals},
     journal = {Applications of Mathematics},
     pages = {406--420},
     publisher = {mathdoc},
     volume = {24},
     number = {6},
     year = {1979},
     doi = {10.21136/AM.1979.103824},
     mrnumber = {0547044},
     zbl = {0449.41003},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/AM.1979.103824/}
}