Composite planar coverings of graphs
نویسنده
چکیده
We shall prove that a connected graph G is projective-planar if and only if it has a 2n-fold planar connected covering obtained as a composition of an n-fold covering and a double covering for some n¿ 1 and show that every planar regular covering of a nonplanar graph is such a composite covering. c © 2002 Elsevier Science B.V. All rights reserved.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 268 شماره
صفحات -
تاریخ انتشار 2003