@article{1077473608,
author = {Lee, H. C.},
title = {Contact transformations},
journal = {Duke Math. J.},
volume = {13},
number = {1},
year = {1946},
pages = { 161-170},
language = {en},
url = {http://dml.mathdoc.fr/item/1077473608}
}
Lee, H. C. Contact transformations. Duke Math. J., Tome 13 (1946) no. 1, pp. 161-170. http://gdmltest.u-ga.fr/item/1077473608/