A Numerical Algorithm for Ambrosetti-Prodi Type Operators
  We consider the numerical solution of the equation - \Delta u - f(u) = g, for the unknown u satisfying Dirichlet conditions in a bounded domain. The nonlinearity f has bounded, continuous derivative. The algorithm uses the finite element method combined with a global Lyapunov-Schmidt decomposition. 
J. Cal Neto, C. Tomei
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