@article{10_4153_CJM_1997_045_9,
     author = {Goulden, I. P. and Jackson, D. M.},
     title = {Maps in {Locally} {Orientable} {Surfaces} and {Integrals} {Over} {Real} {Symmetric} {Surfaces}},
     journal = {Canadian journal of mathematics},
     pages = {865--882},
     year = {1997},
     volume = {49},
     number = {5},
     doi = {10.4153/CJM-1997-045-9},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1997-045-9/}
}