Donoghue $m$-functions for singular Sturm--Liouville operators

Fritz Gesztesy, Lance L. Littlejohn, Roger Nichols +2

Let $\dot{A}$ be a densely defined, closed, symmetric operator in the complex, separable Hilbert space $\mathcal{H}$ with equal deficiency indices and denote by $\mathcal{N}_i = \ke…