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{\bf Marcelo H. de Carvalho and C. H. C. Little}
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{\bf Ear Decompositions in Combed Graphs}
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We introduce the concept of combed graphs and present an ear
decomposition theorem for this class of graphs.  This theorem includes
the well known ear decomposition theorem for matching covered graphs
proved by Lov\'asz and Plummer. Then we use the ear decomposition
theorem to show that any two edges of a 2-connected combed graph lie
in a balanced circuit of an equivalent combed graph.  This result
generalises the theorem that any two edges in a matching covered graph
with at least four vertices belong to an alternating circuit.


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