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A note on čech and kan extensions of homotopy functors

✍ Scribed by Allan Calder; Jerrold Siegel

Publisher
Elsevier Science
Year
1982
Tongue
English
Weight
96 KB
Volume
25
Category
Article
ISSN
0022-4049

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A note on possible extensions of Negami'
A note on possible extensions of Negami's conjecture
✍ Hlin?n�, Petr 📂 Article 📅 1999 🏛 John Wiley and Sons 🌐 English ⚖ 239 KB 👁 2 views

A graph H is a cover of a graph G, if there exists a mapping ϕ from V (H) onto V (G) such that for every vertex v of G, ϕ maps the neighbors of v in H bijectively onto the neighbors of ϕ(v) in G. Negami conjectured in 1987 that a connected graph has a finite planar cover if and only if it embeds in