“…The approximation behavior of operator is well known and direct and converse results, saturation statements and simultaneous approximation estimates not possible by polynomials and corresponding to several nodes meshes distributions can be found for example in [ 1 , 2 , 4 – 7 , 13 , 27 ]. Applications to scattered data interpolation problems, CAGD and image compression were also examined (see e.g.…”