BibTex format
@article{Gay-Balmaz:2012:10.1007/s00220-011-1313-y,
author = {Gay-Balmaz, F and Holm, DD and Meier, DM and Ratiu, TS and Vialard, F-X},
doi = {10.1007/s00220-011-1313-y},
journal = {COMMUNICATIONS IN MATHEMATICAL PHYSICS},
pages = {413--458},
title = {Invariant Higher-Order Variational Problems},
url = {http://dx.doi.org/10.1007/s00220-011-1313-y},
volume = {309},
year = {2012}
}