@article{SM_1984_49_2_a4,
     author = {V. G. Turaev and O. Ya. Viro},
     title = {Intersection of loops in two-dimensional {manifolds.~II.} {Free} loops},
     journal = {Sbornik. Mathematics},
     pages = {357--366},
     publisher = {mathdoc},
     volume = {49},
     number = {2},
     year = {1984},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/SM_1984_49_2_a4/}
}