@article{RSMUP_1999__101__63_0,
     author = {Firlej, B. and Le\'sniewicz, M. and Rempulska, L.},
     title = {Approximation of functions of two variables by some operators in weighted spaces},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {63--82},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {101},
     year = {1999},
     mrnumber = {1705280},
     zbl = {0934.41017},
     language = {en},
     url = {http://www.numdam.org/item/RSMUP_1999__101__63_0/}
}