@article{01505610,
title = {Double coverings and reflexive abelian hypermaps.},
journal = {Beitr\"age zur Algebra und Geometrie},
volume = {41},
year = {2000},
pages = {371-389},
zbl = {0967.05027},
language = {en},
url = {http://dml.mathdoc.fr/item/01505610}
}
Breda d'Azevedo, Antonio J.; Jones, Gareth A. Double coverings and reflexive abelian hypermaps.. Beiträge zur Algebra und Geometrie, Tome 41 (2000) pp. 371-389. http://gdmltest.u-ga.fr/item/01505610/