@InProceedings{doczkal:LIPIcs.ITP.2021.17,
  author =	{Doczkal, Christian},
  title =	{{A Variant of Wagner’s Theorem Based on Combinatorial Hypermaps}},
  booktitle =	{12th International Conference on Interactive Theorem Proving (ITP 2021)},
  pages =	{17:1--17:17},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-188-7},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{193},
  editor =	{Cohen, Liron and Kaliszyk, Cezary},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2021.17},
  URN =		{urn:nbn:de:0030-drops-139123},
  doi =		{10.4230/LIPIcs.ITP.2021.17},
  annote =	{Keywords: Coq, MathComp, Graph-Theory, Hypermaps, Planarity}
}