@article{10_1017_S0017089501030038,
     author = {May, Coy L.},
     title = {The symmetric crosscap number of a group},
     journal = {Glasgow mathematical journal},
     pages = {399--410},
     year = {2001},
     volume = {43},
     number = {3},
     doi = {10.1017/S0017089501030038},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089501030038/}
}