@article{1103037346, author = {Weinzweig, A. I.}, title = {The fundamental group of a union of spaces.}, journal = {Pacific J. Math.}, volume = {11}, number = {4}, year = {1961}, pages = { 763-776}, language = {en}, url = {http://dml.mathdoc.fr/item/1103037346} }
Weinzweig, A. I. The fundamental group of a union of spaces.. Pacific J. Math., Tome 11 (1961) no. 4, pp. 763-776. http://gdmltest.u-ga.fr/item/1103037346/