@article{MABA_2011_25_1-2_a2,
     author = {P.Parvanov},
     title = {Weighted {Approximation} by a {Class} of {Bernstein-Type} {Operators}},
     journal = {Mathematica balkanica},
     pages = {31},
     publisher = {mathdoc},
     volume = {25},
     number = {1-2},
     year = {2011},
     url = {http://geodesic.mathdoc.fr/item/MABA_2011_25_1-2_a2/}
}