Orthogonal Systems and Convolution Operators

1 Orthogonal Polynomials and Krein's Theorem.- 2 Reformulations of Krein's Theorem.- 3 Inner Products on Modules and Orthogonalization with Invertible Squares.- 4 Orthogonal Matrix Polynomials.- 5 Special Class of Block Toeplitz Matrices.- 6 Orthogonal Operator-Valued Polynomials: First Generalization.- 7 Convolution Equations on a Finite Interval.- 8 Continuous Analogues of Orthogonal Matrix Polynomials.- 9 Orthogonal Operator-Valued Polynomials.- 10 Reverse, Left and Right Orthogonalization.- 11 Discrete Infinite Analogue of Krein's Theorem.- 12 Continuous Infinite Analogue of Krein's Theorem.- References.- Index of Symbols.