“…First, superposition methods, such as the method of finite element patches [34,53] and the method of harmonic patches [38], consist in adding a fine local correction to a coarse global solution. Second, surface coupling methods include the Chimera-Schwarz method [11,72], the Semi-Schwarz method [66], the Semi-Schwarz-Lagrange method [29,30,36,55] and the local multigrid method [35,64,65,67]. Both multiscale superposition and surface coupling methods are based on global-local iterative algorithms originally developed for domain decomposition methods or multigrid methods.…”