, Volume 6, Issue 2, pp 119–132 | Cite as

Diagrams, orientations, and varieties

  • Hans-Jürgen Bandelt
  • Ivan Rival


One of the central problems in the theory of ordered sets is to describe the orientations of the covering graph of an ordered set. We show that the particular operation called ‘inversion’, together with the classical constructions of retraction and product, provide a context for the classification of all such orientations.

Key words

Covering graph diagram retract product orientation inversion variety alternating cover cycle cycle 


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Copyright information

© Kluwer Academic Publishers 1989

Authors and Affiliations

  • Hans-Jürgen Bandelt
    • 1
  • Ivan Rival
    • 2
  1. 1.Department of MathematicsUniversity of MaastrichtMaastrichtThe Netherlands
  2. 2.Department of Computer ScienceUniversity of OttawaOttawaCanada

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