@article{1029003288, author = {Loveland, L. D.}, title = {Sets in $E^3$ that locally lie on flat spheres.}, journal = {Michigan Math. J.}, volume = {33}, number = {1}, year = {1986}, pages = { 37-46}, language = {en}, url = {http://dml.mathdoc.fr/item/1029003288} }
Loveland, L. D. Sets in $E^3$ that locally lie on flat spheres.. Michigan Math. J., Tome 33 (1986) no. 1, pp. 37-46. http://gdmltest.u-ga.fr/item/1029003288/