@article{1077491743,
author = {Whittemore, James K.},
title = {Bertrand curves and helices},
journal = {Duke Math. J.},
volume = {6},
number = {1},
year = {1940},
pages = { 235-245},
language = {en},
url = {http://dml.mathdoc.fr/item/1077491743}
}
Whittemore, James K. Bertrand curves and helices. Duke Math. J., Tome 6 (1940) no. 1, pp. 235-245. http://gdmltest.u-ga.fr/item/1077491743/