@article {GhouilaHouri,
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}

@misc{finschi:enumeration,
author = {Lukas Finschi}, 
title = {Catalog of Oriented Matroids}, 
note = {Available at \url{http://www.om.math.ethz.ch/}},
year = {2001}
}

}

@article{simoes,
year={1972},
issn={0025-5874},
journal={Mathematische Zeitschrift},
volume={127},
number={4},
title={On subgraphs as matroid cells},
publisher={Springer-Verlag},
author={Sim\~{o}es Pereira, J.M.S.},
pages={315-322},
language={English}
}

@book{aigner,
   title = "Combinatorial theory",
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}

@book{BLSW,
	title = {Oriented Matroids},
	isbn = {0521418364},
	publisher = {Cambridge University Press},
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	pages = {528}
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@book{west,
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}   

@misc{geelen:blog,
      title  = "Matroids with no \protect{$M(K_4)$}-minor",
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    }

@article{Bollobás1980195, 
title = "Hadwiger's Conjecture is True for Almost Every Graph ", 
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year = "1980", 
author = "B. Bollob\'as and P.A. Catlin and P. Erd\H{o}s", 
}

@article{boergerband, 
author = {Luis Goddyn and Winfried Hochst\"attler}, 
title = {Nowhere-zero flows in regular matroids and Hadwiger's Conjecture}, 
journal = {Seminarberichte der Mathematik -- FernUniversit\"at in Hagen}, 
volume = {87},
pages = {97 -- 102},
year = {2015}
}

@article{honi, 
author = {Winfried Hochst\"attler and Robert Nickel}, 
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number = {1},
pages = {68--86},
year = {2007}
}

@article{honijct,
  author    = {Winfried Hochst{\"a}ttler and
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  volume    = {98},
  number    = {4},
  year      = {2008},
  pages     = {698-706},
}
@article{honese,
 author = {Winfried Hochst\"{a}ttler and Jaroslav Ne\v{s}et\v{r}il},
 title = {Antisymmetric flows in matroids},
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 }

@book {om,
    AUTHOR = {Bj{\"o}rner, Anders and Las Vergnas, Michel and Sturmfels,
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     TITLE = {Oriented matroids},
 PUBLISHER = {Cambridge University Press},
   ADDRESS = {Cambridge},
      YEAR = {1999},
   EDITION = {2nd},
     PAGES = {xii+548},
}

@article{Hlineny,
 author = {Luis Goddyn and Petr Hlin\v{e}n\'{y} and Winfried Hochst\"{a}ttler},
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 journal = {Comb. Probab. Comput.},
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 year = 2006,
 pages = {523--539},
 publisher = {Cambridge University Press},
 address = {New York, NY, USA},
 }

@article{laura,
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	author = {Ch\'avez-Lomel\'i, L. and Goddyn, L. and Hochst\"attler, W.},
	month = jan,
	year = {2011},
	pages = {1315--1318},
}

@article{folklaw, 
  author = {Folkman, Jon and Lawrence, Jim},
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  volume = {25},
  year = {1978},
  number = {2},
  pages = {199--236}
}

@article{ bland:orientability,
author = {Robert G. Bland and Michel Las Vergnas},
title = {Orientability of matroids},
journal = {Journal of Combinatorial Theory Series B},
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year = {1978},
pages = {94--123},
publisher = {Academic Press, Inc.},
}

@book {oxley,
    AUTHOR = {Oxley, James G.},
     TITLE = {Matroid theory},
 PUBLISHER = {The Clarendon Press Oxford University Press},
   ADDRESS = {New York},
      YEAR = {1992},
     PAGES = {xii+532},
}

@book {diestel,
	edition = {3rd},
	title = {Graph Theory},
	isbn = {3540261834},
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	year = {2006}
}

@article{crapo_tutte_1969,
	title = {The Tutte polynomial},
	volume = {3},
	number = {3},
	journal = {Aequationes Mathematicae},
	author = {Henry H. Crapo},
	month = oct,
	year = {1969},
	pages = {314}
}

@inproceedings{tutte3,
author = "W.T. Tutte",
title = "A geometrical Version of the Four Color Problem", 
booktitle =  "Combinatorial Math. and Its Applications",
editor = "R. C. Bose and T. A. Dowling",
pages = {553 -- 560},
year = "1967",
organization = "Chapel Hill, NC: University of North Carolina Press"
}


@article{tutte2,
title = "On the algebraic theory of graph colorings",
journal = "Journal of Combinatorial Theory",
volume = "1",
number = "1",
pages = "15 - 50",
year = "1966",
author = "W.T. Tutte"
}
@mastersthesis{Kilpatrick,
	title = {Tutte's first colour-cycle conjecture.},
	author = {Kilpatrick, Peter Allan},
	year = {1975},
	keywords = {Mathematics and Applied Mathematics.},
	school = {University of Cape Town}
}
@article {SeymourNZ6,
    AUTHOR = {Seymour, P. D.},
     TITLE = {Nowhere-zero {$6$}-flows},
   JOURNAL = {J. Combin. Theory Ser. B},
  FJOURNAL = {Journal of Combinatorial Theory. Series B},
    VOLUME = 30,
      YEAR = 1981,
    NUMBER = 2,
     PAGES = {130--135},
      ISSN = {0095-8956},
     CODEN = {JCBTB8},
   MRCLASS = {05C38 (05C20 90B10)},
  MRNUMBER = {MR615308 (82j:05079)},
MRREVIEWER = {Fran{\c{c}}ois Jaeger},
}

@article{Jaeger,
title = "Flows and generalized coloring theorems in graphs",
journal = "Journal of Combinatorial Theory, Series B",
volume = "26",
number = "2",
pages = "205 - 216",
year = "1979",
author = "F. Jaeger"
}

@Article{Tutte:dichromate,
  author = 	 {W.T. Tutte},
  title = 	 {A contribution to the theory of chromatic polynomials},
  journal = 	 {Canad. J. Math.},
  year = 	 {1954},
  volume = 	 {6},
  pages = 	 {80-91},
}

@Article{Tutte:Abelian,
  author = 	 {W.T. Tutte},
  title = 	 {A class of Abelian groups},
  journal = 	 {Canad. J. Math.},
  year = 	 {1956},
  volume = 	 {8},
  pages = 	 {13-28},
}

@article{robertson_four-colour_1997,
	title = {The {Four-Colour} Theorem},
	volume = {70},
	issn = {0095-8956},
	number = {1},
	journal = {Journal of Combinatorial Theory, Series B},
	author = {Neil Robertson and Daniel Sanders and Paul Seymour and Robin Thomas},
	month = may,
	year = {1997},
	pages = {2--44}
}

@article{appel_every_1976,
	title = {Every planar map is four colorable},
	journal = {Bull. Amer. Math. Soc.},
        volume = 82, 
        number = 5, 
	author = {Kenneth I. Appel and Wolfgang Haken},
	year = 1976,
	pages = {711-712}
}

@article{wagner_ber_1937,
	title = {{\"Uber eine Eigenschaft der ebenen Komplexe}},
	volume = 114,
	number = 1,
	journal = {Mathematische Annalen},
	author = {K. Wagner},
	month = dec,
	year = 1937,
	pages = {570--590}
}

@ARTICLE{Hadwiger,
    author = {Hugo Hadwiger},
    title = {{\"Uber eine Klassifikation der Streckenkomplexe}},
    journal = {Vierteljahresschrift der Naturforschenden Gesellschaft in Z\"urich},
    year = 1943,
    volume = 88,
    pages = {133--142}
}
@ARTICLE{RST,
    author = {Neil Robertson and Paul Seymour and Robin Thomas},
    title = {Hadwiger's conjecture for \protect{$K_6$}-free graphs},
    journal = {Combinatorica},
    year = 1993,
    volume = 13,
    pages = {279--361}
}
@article{wang_nowhere-zero_2009,
	title = {Nowhere-zero 4-flow in almost Petersen-minor free graphs},
	volume = {309},
	number = {5},
	journal = {Discrete Mathematics},
	author = {Xiaofeng Wang and {Cun-Quan} Zhang and Taoye Zhang},
	month = mar,
	year = {2009},
	keywords = {4-flow, Almost Petersen-minor free graphs, Edge-3-coloring, Integer flow, Petersen minor},
	pages = {1025--1032}
},

@book{white_combinatorial_1987,
	title = {Combinatorial Geometries},
	isbn = {0521333393},
	lccn = {0095},
	publisher = {Cambridge University Press},
	author = {White, Neil},
	month = sep,
	year = {1987}
}


@article{arrowsmith_enumeration_1982,
	title = {On the enumeration of chains in regular chain-groups},
	volume = {32},
	number = {1},
	journal = {Journal of Combinatorial Theory, Series B},
	author = {Arrowsmith, {D.K} and Jaeger, F},
	month = feb,
	year = {1982},
	pages = {75--89},
}


@book{Schrijver,
	title = {Theory of Linear and Integer Programming},
	isbn = {0471982326},
	lccn = {4998},
	publisher = {Wiley},
	author = {Schrijver, Alexander},
	month = jun,
	year = {1998}
}

@article{lason2014indicated,
  title={Indicated coloring of matroids},
  author={Laso{\'n}, Micha{\l}},
  journal={Discrete Applied Mathematics},
  volume={179},
  number={2014},
  pages={241--243},
  year={2014},
  publisher={arXiv:1302.3811}
}

@misc{kiralipap,
author = {Kir\'ali, Tam\'as and Pap, J\'ulia}, 
title = {On the list coloring of two matroids},
howpublished = {EGRES Quick-Proof No.\ 2010-01},
note = {Available at \url{http://lemon.cs.elte.hu/egres/open/List_colouring_of_two_matroids}},
year = {2010 (accessed November 22, 2015)}
}

@book{welsh1976matroid,
  title={Matroid theory},
  author={Welsh, D.J.A.},
  isbn={9780127440507},
  lccn={lc76010493},
  series={L.M.S. monographs},
  year={1976},
  publisher={Academic Press}
}

@article {goddyntarsizhang,
author = {Goddyn, Luis A. and Tarsi, Michael and Zhang, Cun-Quan},
title = {On (k, d)-colorings and fractional nowhere-zero flows},
journal = {Journal of Graph Theory},
volume = {28},
number = {3},
publisher = {Wiley Subscription Services, Inc., A Wiley Company},
issn = {1097-0118},
pages = {155--161},
keywords = {star chromatic number, nowhere-zero flow, (k, d)-coloring oriented graphs, orientable matroids, regular matroids},
year = {1998},
}