@article{article68e731bd,
title   = {Canonical form of Euler-Langrange equations and gauge symmetries},
author = {Geyer, B and Gitman, Dmitri Maximovitch and Tyutin, I V},
year = {2003},
doi = {10.1088/0305-4470/36/23/321},
journal   = {Journal of Physics A}
}