The necessity of non-Abelian groups in the case 0 of the heawood map-coloring theorem
1972 ◽
Vol 13
(3)
◽
pp. 263-265
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1985 ◽
Vol 58
(3)
◽
pp. 131-145
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1995 ◽
Vol 44
(2)
◽
pp. 395-402
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Keyword(s):
1978 ◽
Vol 29
(6)
◽
pp. 541-544
◽
Keyword(s):
Keyword(s):