@article{1103037340, author = {Martin, N. F. G.}, title = {Lebesgue density as a set function.}, journal = {Pacific J. Math.}, volume = {11}, number = {4}, year = {1961}, pages = { 699-704}, language = {en}, url = {http://dml.mathdoc.fr/item/1103037340} }
Martin, N. F. G. Lebesgue density as a set function.. Pacific J. Math., Tome 11 (1961) no. 4, pp. 699-704. http://gdmltest.u-ga.fr/item/1103037340/