@article{SMJ2_1995_21_2_a3,
     author = {Gonska, Heinz and Zhou, Ding-Xuan},
     title = {On an {Extremal} {Problem} concerning {Bernstein} {Operators}},
     journal = {Serdica Mathematical Journal},
     pages = {137--150},
     publisher = {mathdoc},
     volume = {21},
     number = {2},
     year = {1995},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SMJ2_1995_21_2_a3/}
}