@article{SM_1992_71_2_a2,
     author = {N. V. Ivanov},
     title = {Permutation representations of braid groups of surfaces},
     journal = {Sbornik. Mathematics},
     pages = {309--318},
     publisher = {mathdoc},
     volume = {71},
     number = {2},
     year = {1992},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1992_71_2_a2/}
}