@InCollection{ Gubisch.Neitzel.Volkwein:2016, author = {Gubisch, Martin and Neitzel, Ira and Volkwein, Stefan}, title = {A-posteriori error estimation of discrete POD models for PDE-constrained optimal control}, booktitle = {Model reduction and approximation: theory and algorithms}, series = {Computational Science and Engineering}, volume = {}, pages = {}, publisher = {SIAM}, year = {}, annote = {series}, pdf = {http://neitzel.ins.uni-bonn.de/pub/GNV2016_INS.pdf}, note = {accepted. Preprint version available as INS Preprint No. 1608.}, inspreprintnum= {1608} }