  Representations of equipped graphs were introduced by Gelfand and Ponomarev;
they are similar to representation of quivers, but one does not need to choose
an orientation of the graph. In a previous article we have shown that, as in
Kac's Theorem for quivers, the dimension vectors of indecomposable
representations are exactly the positive roots for the graph. In this article
we begin by surveying that work, and then we go on to discuss Auslander-Reiten
theory for equipped graphs, and give examples of Auslander-Reiten quivers.
