Existence results for quasilinear elliptic systems in ℝ N . Stavrakakis, N.M.; Zographopoulos, N.B. — 1999 Electronic Journal of Differential Equations (EJDE) [electronic only]
The first eigenvalue of p -Laplacian systems with nonlinear boundary conditions. Kandilakis, D.A.; Magiropoulos, M.; Zographopoulos, N.B. — 2005 Boundary Value Problems [electronic only]