LIST EDGE AND LIST TOTAL COLORINGS OF PLANAR GRAPHS WITHOUT 6-CYCLES WITH CHORD

Giving a planar graph G, let ' ( G) and '' ( G) denote the list edge chromatic number and list total chromatic number of G respectively. It is proved that if a planar graph G without 6-cycles with chord, then ' l ( G) ∆( G) + 1 and '' l ( G) ∆( G) + 2 where ∆( G) 6.