1. APPROXIMATION PROCEDURES IN CONNECTION WITH A PROBLEM OF STURM-LIOUVILLE TYPE. Authors: ALEXANDRU IOAN MITREA.2. ON THE DIVERGENCE OF THE PRODUCT QUADRATURE PROCEDURES. Authors: ALEXANDRU IOAN MITREA.3. ON THE POINTWISE CONVERGENCE OF THE CHEBYSHEV BEST APPROXIMATION ON JACOBI NODES. Authors: ALEXANDRU IOAN MITREA.