@unpublished{138r_PREPRINT,
 Author = {Marco Bernreuther and Georg M\"{u}ller and Stefan Volkwein},
 Note = {Preprint SPP1962-138r},
 Title = {Reduced Basis Model Order Reduction in Optimal Control of a Nonsmooth Semilinear Elliptic PDE},
 Month = {4},
 Year = {2021}}