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[35] I. Perugia and D. Schötzau. The hp-local discontinuous Galerkin method for low-frequency time-harmonic Maxwell equations. *Math. Comp.*, 72(243):1179–1214, 2003.

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[38] J. Schöberl. A posteriori error estimates for Maxwell equations. *Math. Comp.*, 77(262):633–649, 2007.

[39] C. Weber. A local compactness theorem for Maxwell’s equations. *Math. Methods Appl. Sci.*, 2(1):12–25, 1980.