Viliam Geffert Andreas Malcher Katja Meckel Carlo Mereghetti Beatrice Palano A Direct Construction of Finite State Automata for Pushdown Store Languages. 90-101 2013 DCFS https://doi.org/10.1007/978-3-642-39310-5_10 conf/dcfs/2013 db/conf/dcfs/dcfs2013.html#GeffertMMMP13