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Harary, Frank. «14. Groups - Symmetric graphs». A: Graph theory. Addison Wesley, 1969, p. 172. ISBN 9780201410334 [Consulta: 1r juliol 2016]. «Theorem 14.12: Every line-symmetric graph with no isolated points is point-
symmetric or bipartite.»Arxivat 2017-02-07 a Wayback Machine.
Harary, Frank. «14. Groups - Symmetric graphs». A: Graph theory. Addison Wesley, 1969, p. 172. ISBN 9780201410334 [Consulta: 1r juliol 2016]. «Theorem 14.12: Every line-symmetric graph with no isolated points is point-
symmetric or bipartite.»Arxivat 2017-02-07 a Wayback Machine.