@article{BUMI_2012_9_5_2_a12,
     author = {Bonora, Loriano and Ferrari Ruffino, Fabio and Savelli, Raffaele},
     title = {Revisiting {Pinors} and {Orientability}},
     journal = {Bollettino della Unione matematica italiana},
     pages = {405--422},
     publisher = {mathdoc},
     volume = {Ser. 9, 5},
     number = {2},
     year = {2012},
     zbl = {1261.57022},
     mrnumber = {2977256},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/BUMI_2012_9_5_2_a12/}
}