Approximation by Multivariate Singular Integrals

-1. Uniform Approximation by General Multivariate Singular Integral Operators(Introduction, Main Results, Applications, References). -2. Approximation by General Multivariate Singular Integral Operators(Introduction, Main Results, Applications, References). -3. Global Smoothness Preservation and Simultaneous Approximation by Multivariate General Singular Integrals(Introduction, Main Results, Applications, References). -4. Multivariate Voronovskaya Asymptotic Expansions for General Singular Integrals (Introduction, Main Results, Applications, References).-5. Simultaneous Approximation by Multivariate Complex General Singular Integrals (Introduction, Main Results, Applications, References). -6. Approximation of Functions of Two Variables via Almost Convergence of Double Sequences (Introduction and Preliminaries, Korovkin type approximation theorem, Some consequences, References).