+%%NEW\r
+\r
+\subsection{Parallel nonlinear problems}\r
+\r
+With PETSc, linear solvers are used inside nonlinear solvers. The SNES\r
+(Scalable Nonlinear Equations Solvers) module in PETSc implements easy to use\r
+methods, like Newton-type, quasi-Newton or full approximation scheme (FAS)\r
+multigrid to solve systems of nonlinears equations. As the SNES is based on the\r
+Krylov methods of PETSc, it is interesting to investigate if the TSIRM method is\r
+also efficient and scalable with non linear problems.\r
+\r
+\r
+\r