We prove the simplicity and isolation of the first eigenvalue for the problem Δ pu = |u| p-2u in a bounded smooth domain Ω 〈 ℝ N, with a nonlinear boundary condition given by |∇u| p-2∂u/∂v = λ |u| p-2u on the boundary of the domain. Copyright © 2002 Hindawi Publishing Corporation.
Martínez, S., & Rossi, J. D. (2002). Isolation and simplicity for the first eigenvalue of the p-laplacian with a nonlinear boundary condition. Abstract and Applied Analysis, 7(5), 287–293. https://doi.org/10.1155/S108533750200088X