M. Langer and A. Luger,
Scalar generalized Nevanlinna functions: realizations with block operator matrices,
Oper. Theory Adv. Appl. 162 (2006), 253–276

Abstract:
In this paper a concrete realization for a scalar generalized Nevanlinna function qNκ is given using the realizations of the factors in the basic factorization of q. Some cases are discussed in more detail and the representing operators are given as block operator matrices.

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