Collapse Operation Increases Expressive Power of Deterministic Higher Order Pushdown Automata

@InProceedings{parys:LIPIcs.STACS.2011.603,
  author =	{Parys, Pawel},
  title =	{{Collapse Operation Increases Expressive Power of Deterministic Higher Order Pushdown Automata}},
  booktitle =	{28th International Symposium on Theoretical Aspects of Computer Science (STACS 2011)},
  pages =	{603--614},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-939897-25-5},
  ISSN =	{1868-8969},
  year =	{2011},
  volume =	{9},
  editor =	{Schwentick, Thomas and D\"{u}rr, Christoph},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2011.603},
  URN =		{urn:nbn:de:0030-drops-30478},
  doi =		{10.4230/LIPIcs.STACS.2011.603},
  annote =	{Keywords: pushdown automata}
}