On the completeness of elementary solutions of a class of second-order differential equations with operator coefficients. (English. Russian original) Zbl 1201.34133
Math. Notes 86, No. 5, 747-750 (2009); translation from Mat. Zametki 86, No. 5, 797-800 (2009).
Reviewer: Zoran Kadelburg (Beograd)