00630nam a2200337Ia 4500010000500000020001800005082001900023100002200042110000500064245005300069250000500122260004200127300002800169490000500197500000500202600000500207610000500212611000500217630000500222650000500227651000500232654000500237700000900242710000900251711000500260720000500265730000500270740000500275752000500280856000700285  a  a9780198510628  a511.5bW752.GC  aWilson, Robert A.  a  aGraphs, colourings and the four-colour theoremb  a  aOxfordbOxford University Pressc2004  aviii, 141p. Bibl. Index  a  a  a  a  a  a  a  a  a  abc  abc  a  a  a  a  a  df