@article{02166322, title = {Fundamental groupoids of }, journal = {The New York Journal of Mathematics [electronic only]}, volume = {10}, year = {2004}, pages = {195-207}, zbl = {1064.05073}, language = {en}, url = {http://dml.mathdoc.fr/item/02166322} }
Pask, David; Quigg, John; Raeburn, Iain. Fundamental groupoids of . The New York Journal of Mathematics [electronic only], Tome 10 (2004) pp. 195-207. http://gdmltest.u-ga.fr/item/02166322/