| Title: | On chirality groups and regular coverings of regular oriented hypermaps (English) | 
| Author: | Breda d'Azevedo, Antonio | 
| Author: | Rodrigues, Ilda Inácio | 
| Author: | Fernandes, Maria Elisa | 
| Language: | English | 
| Journal: | Czechoslovak Mathematical Journal | 
| ISSN: | 0011-4642 (print) | 
| ISSN: | 1572-9141 (online) | 
| Volume: | 61 | 
| Issue: | 4 | 
| Year: | 2011 | 
| Pages: | 1037-1047 | 
| Summary lang: | English | 
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| Category: | math | 
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| Summary: | We prove that if the Walsh bipartite map $\mathcal {M}=\mathcal {W}(\mathcal {H})$ of a regular oriented hypermap $\mathcal {H}$ is also orientably regular then both $\mathcal {M}$ and $\mathcal {H}$ have the same chirality group, the covering core of $\mathcal {M}$ (the smallest regular map covering $\mathcal {M}$) is the Walsh bipartite map of the covering core of $\mathcal {H}$ and the closure cover of $\mathcal {M}$ (the greatest regular map covered by $\mathcal {M}$) is the Walsh bipartite map of the closure cover of $\mathcal {H}$. We apply these results to the family of toroidal chiral hypermaps $(3,3,3)_{b,c}=\mathcal {W}^{-1}\{6,3\}_{b,c}$ induced by the family of toroidal bipartite maps $\{6,3\}_{b,c}$. (English) | 
| Keyword: | hypermap | 
| Keyword: | regular covering | 
| Keyword: | chirality group | 
| Keyword: | chirality index | 
| Keyword: | toroidal hypermaps | 
| MSC: | 05C10 | 
| MSC: | 05C25 | 
| MSC: | 20B25 | 
| MSC: | 20F65 | 
| MSC: | 51E30 | 
| MSC: | 57M07 | 
| MSC: | 57M60 | 
| idZBL: | Zbl 1249.05086 | 
| idMR: | MR2886255 | 
| DOI: | 10.1007/s10587-011-0046-6 | 
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| Date available: | 2011-12-16T15:45:28Z | 
| Last updated: | 2020-07-03 | 
| Stable URL: | http://hdl.handle.net/10338.dmlcz/141805 | 
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