Every Planar Map Is Four Colorable
Keyword(s):
2002 ◽
Vol 15
(5)
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pp. 567-573
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1977 ◽
Vol 21
(3)
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pp. 491-567
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Keyword(s):
1978 ◽
Vol s2-18
(2)
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pp. 193-201
2011 ◽
Vol 225-226
◽
pp. 1274-1278
Keyword(s):
Keyword(s):
Keyword(s):
1981 ◽
Vol 8
(1)
◽
pp. 17-33
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