@article{1138038880, author = {Chen, Bang-Yen}, title = {Null $2$-type surfaces in $E^3$ are circular cylinders}, journal = {Kodai Math. J.}, volume = {11}, number = {1}, year = {1988}, pages = { 295-299}, language = {en}, url = {http://dml.mathdoc.fr/item/1138038880} }
Chen, Bang-Yen. Null $2$-type surfaces in $E^3$ are circular cylinders. Kodai Math. J., Tome 11 (1988) no. 1, pp. 295-299. http://gdmltest.u-ga.fr/item/1138038880/