@article{CTGDC_2009__50_3_171_0, author = {Gran, Marino and Janelidze, George}, title = {Covering morphisms and normal extensions in {Galois} structures associated with torsion theories}, journal = {Cahiers de Topologie et G\'eom\'etrie Diff\'erentielle Cat\'egoriques}, eid = {1}, pages = {171--188}, publisher = {Andr\'ee CHARLES EHRESMANN}, volume = {50}, number = {3}, year = {2009}, mrnumber = {2553538}, zbl = {1197.18007}, language = {en}, url = {http://www.numdam.org/item/CTGDC_2009__50_3_171_0/} }