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Characterization of domains of self-adjoint ordinary differential operators. (English) Zbl 1169.47033
The authors give a characterization of domains for selfadjoint ordinary differential operators. They give a representation in terms of certain solutions for real $\lambda$. This leads to a classification of solutions as limit-point or limit-circle in analogy with the Weyl classification in the second-order case.

##### MSC:
 47E05 Ordinary differential operators 34B20 Weyl theory and its generalizations 34B24 Sturm-Liouville theory 47B25 Symmetric and selfadjoint operators (unbounded)
##### References:
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