20 citations · 50 across the 20 of their papers we have counts for
3 papers · 2 filters
A Toeplitz-like operator with rational matrix symbol having poles on the unit circle: Invertibility and Riccati equations
G. J. Groenewald, S. ter Horst, J. Jaftha +1
This paper is a continuation of the work on unbounded Toeplitz-like operators $T_\Om$ with rational matrix symbol $\Om$ initiated in Groenewald et. al (Complex Anal. Oper. Theory 1…
Wiener-Hopf indices of unimodular functions on the unit circle, revisited
A. E. Frazho, M. A. Kaashoek, A. C. M. Ran +1
Inspired by the paper of Groenewald, Kaashoek and Ran (Wiener-Hopf indices of unitary functions on the unit circle in terms of realizations and related results on Toeplitz operator…
A Toeplitz-like operator with rational matrix symbol having poles on the unit circle: Fredholm characteristics
G. J. Groenewald, S. ter Horst, J. J. Jaftha +1
In a recent paper (Groenewald et al.\ {\em Complex Anal.\ Oper.\ Theory} \textbf{15:1} (2021)) we considered an unbounded Toeplitz-like operator generated by a rational matri…