@article{MABA_2001_15_3-4_a12,
     author = {I. A. Parvanova and P. E. Parvanov},
     title = {Exact {Constants} in {Estimation} of the {Error} of the {Quadrature} {Formulae} of {Simpson} with the {Averaged} {Moduli} of {Smoothness}},
     journal = {Mathematica balkanica},
     pages = {303},
     publisher = {mathdoc},
     volume = {15},
     number = {3-4},
     year = {2001},
     url = {http://geodesic.mathdoc.fr/item/MABA_2001_15_3-4_a12/}
}