Approximation of the resonance boundary-value problems of elliptic type with a discontinuous nonlinearity. Lepchinskii, M.G.; Pavlenko, V.N. — 2005 Sibirskij Matematicheskij Zhurnal
Existence of a ray of eigenvalues for equations with discontinuous operators. Pavlenko, V.N.; Potapov, D.K. — 2001 Sibirskij Matematicheskij Zhurnal