@article{SM_1979_35_2_a5,
     author = {V. G. Turaev},
     title = {Intersections of loops in two-dimensional manifolds},
     journal = {Sbornik. Mathematics},
     pages = {229--250},
     year = {1979},
     volume = {35},
     number = {2},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1979_35_2_a5/}
}