@article{1256054992,
author = {Johnson, H. H.},
title = {Absolute equivalence of exterior differential systems},
journal = {Illinois J. Math.},
volume = {10},
number = {4},
year = {1966},
pages = { 407-411},
language = {en},
url = {http://dml.mathdoc.fr/item/1256054992}
}
Johnson, H. H. Absolute equivalence of exterior differential systems. Illinois J. Math., Tome 10 (1966) no. 4, pp. 407-411. http://gdmltest.u-ga.fr/item/1256054992/