International Journal of Mathematics and Mathematical Sciences
Volume 2005 (2005), Issue 9, Pages 1481-1495

Boundary value problems with regular singularities and singular boundary conditions

G. Freiling1 and V. Yurko2

1Fachbereich Mathematik, Universität Duisburg-Essen, Duisburg 47048, Germany
2Department of Mathematics and Mechanics, Saratov State University, Astrakhanskaya 83, Saratov 410026, Russia

Received 14 May 2004

Copyright © 2005 G. Freiling and V. Yurko. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Singular boundary conditions are formulated for nonselfadjoint Sturm-Liouville operators with singularities and turning points. For boundary value problems with singular boundary conditions, properties of the spectrum are studied and the completeness of the system of root functions is proved.