@InProceedings{kiefer_et_al:LIPIcs.STACS.2019.43,
  author =	{Kiefer, Stefan and Mascle, Corto},
  title =	{{On Finite Monoids over Nonnegative Integer Matrices and Short Killing Words}},
  booktitle =	{36th International Symposium on Theoretical Aspects of Computer Science (STACS 2019)},
  pages =	{43:1--43:13},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-100-9},
  ISSN =	{1868-8969},
  year =	{2019},
  volume =	{126},
  editor =	{Niedermeier, Rolf and Paul, Christophe},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.STACS.2019.43},
  URN =		{urn:nbn:de:0030-drops-102823},
  doi =		{10.4230/LIPIcs.STACS.2019.43},
  annote =	{Keywords: matrix semigroups, unambiguous automata, codes, Restivo’s conjecture}
}