Estimates for the convergence rate of a Fourier series in Laguerre–Sobolev polynomials

Considering the approximation of $f\in W^r_{L^2_w}$, with $w(x)=e^{-x}$, by the partial sums $S_{r,r+n}(f,x)$ of the Fourier series in a system of polynomials orthogonal in the sense of Sobolev and generated by a system of classical Laguerre polynomials, we obtain some estimates for the convergence rate of $S_{r,r+n}(f,x)$ to $f(x)$.