@article{CMUC_1975__16_3_a12,
     author = {Str\'ansk\'a, Carmen},
     title = {Optimal and {Sard} approximation},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {567--582},
     publisher = {mathdoc},
     volume = {16},
     number = {3},
     year = {1975},
     mrnumber = {0425472},
     zbl = {0313.41007},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1975__16_3_a12/}
}