@string{ac="Algorithms and Complexity Group, TU Wien"} @TechReport{Chew21tr, author = {Leroy Chew}, title = {Hardness and Optimality in QBF Proof Systems Modulo NP}, institution = AC, year = {2021}, number = {AC-TR-21-013}, url = {http://www.ac.tuwien.ac.at/files/tr/ac-tr-21-013.pdf}, }