@article{MABA_2002_16_1-4_a2,
     author = {M.D. Takev},
     title = {Direct and {Inverse} {Approximation} {Theorems} in {R2}},
     journal = {Mathematica balkanica},
     pages = {53},
     publisher = {mathdoc},
     volume = {16},
     number = {1-4},
     year = {2002},
     url = {http://geodesic.mathdoc.fr/item/MABA_2002_16_1-4_a2/}
}