Keywords: Herschel graph no col.svg Herschel graph Herschel_graph svg 2010-09-17 10 15 UTC Herschel_graph svg David Eppstein derivative work Koko90 <span class signature-talk >talk</span> 1 color only Koko90 Herschel_graph svg own David Eppstein 2009-10-12 Undirected planar grap</nowiki> Uploaded with derivativeFX Category Herschel graph |