@article{10_4153_CJM_1991_073_0,
     author = {Hansen, Vagn Lundsgaard and V, Peter Petersen},
     title = {Groups, {Coverings} and {Galois} {Theory}},
     journal = {Canadian journal of mathematics},
     pages = {1281--1293},
     year = {1991},
     volume = {43},
     number = {6},
     doi = {10.4153/CJM-1991-073-0},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1991-073-0/}
}