@unpublished{144_PREPRINT,
 Author = {Amal Alphonse and Michael Hinterm\"{u}ller and Carlos N. Rautenberg},
 Note = {Preprint SPP1962-144},
 Title = {Optimal Control and Directional Differentiability for Elliptic Quasi-variational Inequalities},
 Month = {8},
 Year = {2020}}