@Article{ Boffi.Gallistl.Gardini.ea:2015, author = {Boffi, D. and Gallistl, D. and Gardini, F. and Gastaldi, L.}, title = {Optimal convergence of adaptive {FEM} for eigenvalue clusters in mixed form}, journal = {Math. Comp.}, fjournal = {Mathematics of Computation}, year = {2016}, annote = {inspreprint,journal}, archiveprefix = {arXiv}, eprint = {1504.06418}, pdf = {https://arxiv.org/pdf/1504.06418.pdf}, inspreprintnum= {1506}, note = {Accepted for publication} }