@article{10_2140_agt_2004_4_757,
     author = {Gon\c{c}alves, Daciberg Lima and Guaschi, John},
     title = {The braid groups of the projective plane},
     journal = {Algebraic and Geometric Topology},
     pages = {757--780},
     year = {2004},
     volume = {4},
     number = {2},
     doi = {10.2140/agt.2004.4.757},
     url = {http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.757/}
}