Compactness condition for boundary value problems.
(English).
In:
Agarwal, Ravi P., Neuman, F.
and
Vosmanský, J. (eds.):
Proceedings of Equadiff 9,
Conference on Differential Equations and Their Applications, Brno, August 25-29, 1997.
[Part 1] Survey papers.
Masaryk University, Brno, 1998.
pp. 1-23