@article {mclachlan_quispel_robidoux99,
    AUTHOR = {McLachlan, Robert I. and Quispel, G. R. W. and Robidoux,
              Nicolas},
     TITLE = {Geometric integration using discrete gradients},
   JOURNAL = {R. Soc. Lond. Philos. Trans. Ser. A Math. Phys. Eng. Sci.},
  FJOURNAL = {The Royal Society of London. Philosophical Transactions.
              Series A. Mathematical, Physical and Engineering Sciences},
    VOLUME = {357},
      YEAR = {1999},
    NUMBER = {1754},
     PAGES = {1021--1045},
      ISSN = {1364-503X},
   MRCLASS = {34A45 (37M15 65L99 70-08)},
  MRNUMBER = {2000f:34021},
MRREVIEWER = {Steve Shkoller},
}