@article{RM_2006_61_4_a5,
     author = {A. V. Alekseevskii and S. M. Natanzon},
     title = {Algebra of {Hurwitz} numbers for seamed surfaces},
     journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova},
     pages = {767--769},
     publisher = {mathdoc},
     volume = {61},
     number = {4},
     year = {2006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/RM_2006_61_4_a5/}
}