A robust a posteriori estimator for the residual-free bubbles method applied to advection-diffusion problems

We develop the a posteriori error analysis for the RFB method, applied to the linear advection-diffusion problem: the numerical error, measured in suitable norms, is estimated in terms of the numerical residual. The robustness is investiged, in the sense that we prove uniform equivalence between a norm of the numerical residual and a particular norm of the error