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DescriptionK33 parallel edge coloring.svg
English: An edge coloring of the utility graphK3,3, with the property that the edges in each color class are parallel, following the work of Richter, David A. (2011), "How to draw a Tait-colorable graph", in Brandes, Ulrik; Cornelsen, Sabine, Proc. 18th International Symposium on Graph Drawing (GD 2010), Lecture Notes in Computer Science, 6502, Springer-Verlag, pp. 353–364, doi:10.1007/978-3-642-18469-7_32.
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{{Information |Description ={{en|1=An edge coloring of the utility graph ''K''<sub>3,3</sub>, with the property that the edges in each color class are parallel, following the work of Richter, David A. (2011),