@article{1102970755, author = {Stein, Sherman K.}, title = {$B$-sets and planar maps.}, journal = {Pacific J. Math.}, volume = {39}, number = {3}, year = {1971}, pages = { 217-224}, language = {en}, url = {http://dml.mathdoc.fr/item/1102970755} }
Stein, Sherman K. $B$-sets and planar maps.. Pacific J. Math., Tome 39 (1971) no. 3, pp. 217-224. http://gdmltest.u-ga.fr/item/1102970755/