A graph is 1-planar if it can be embedded in the plane so that each edge is crossed by at most one other edge. We prove that each 1-planar graph of minimum degree 5 and girth 4 contains (1) a 5-vertex adjacent to an ≤ 6-vertex, (2) a 4-cycle whose every vertex has degree at most 9, (3) a with all vertices having degree at most 11.
@article{bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1454, author = {D\'avid Hud\'ak and Tom\'as Madaras}, title = {On local structure of 1-planar graphs of minimum degree 5 and girth 4}, journal = {Discussiones Mathematicae Graph Theory}, volume = {29}, year = {2009}, pages = {385-400}, zbl = {1194.05025}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1454} }
Dávid Hudák; Tomás Madaras. On local structure of 1-planar graphs of minimum degree 5 and girth 4. Discussiones Mathematicae Graph Theory, Tome 29 (2009) pp. 385-400. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_7151_dmgt_1454/
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