@article{MZ_1966__94_170609,
     author = {A. Sch\"onhage},
     title = {Lebesguekonstanten bei numerischer {Differentiation.}},
     journal = {Mathematische Zeitschrift},
     pages = {79--83},
     publisher = {mathdoc},
     volume = {94},
     year = {1966},
     zbl = {0141.33501},
     url = {http://geodesic.mathdoc.fr/item/MZ_1966__94_170609/}
}