Partial Non-stationary Perturbation Determinants for a Class of J-symmetric Operators -- Reproducing Kernel Spaces of Series of Fueter Polynomials -- Extremal Extensions of a C(?)-suboperator and Their Representations -- A Variational Principle for Linear Pencils of Forms -- Selfadjoint Extensions with Several Gaps: Finite Deficiency Indices -- The Spectrum of the Multiplication Operator Associated with a Family of Operators in a Banach Space -- A Factorization Model for the Generalized Friedrichs Extension in a Pontryagin Space -- Generalized Schur Functions and Augmented Schur Parameters -- On Nonmonic Quadratic Matrix Polynomials with Nonnegative Coefficients -- On Operator Representations of Locally Definitizable Functions -- Symmetric Relations of Finite Negativity -- An Operator-theoretic Approach to a Multiple Point Nevanlinna-Pick Problem for Generalized Carathéodory Functions -- Bounded Normal Operators in Pontryagin Spaces -- Scalar Generalized Nevanlinna Functions: Realizations with Block Operator Matrices -- Polar Decompositions of Normal Operators in Indefinite Inner Product Spaces -- Bounds for Contractive Semigroups and Second-Order Systems.