Graph homomorphisms: structure and symmetry

@inproceedings{Hahn1997GraphHS,
  title={Graph homomorphisms: structure and symmetry},
  author={Gena Hahn and Claude Tardif},
  year={1997}
}
This paper is the first part of an introduction to the subject of graph homomorphism in the mixed form of a course and a survey. We give the basic definitions, examples and uses of graph homomorphisms and mention some results that consider the structure and some parameters of the graphs involved. We discuss vertex-transitive graphs and Cayley graphs and their rather fundamental role in some aspects of graph homomorphisms. Graph colourings are then explored as homomorphisms, followed by a… 

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