@article{BBHMWZA09,
    author      = {Bostan, A. and Boukraa, S. and Hassani, S. and Maillard,
  J.-M. and Weil, J.-A. and Zenine, N. and Abarenkova, N.},
    title       = {Renormalization, isogenies and rational symmetries of
  differential equations},
    journal     = {Advances in Mathematical Physics},
    number      = {ID 941560},
    pages       = {44pp},
    year        = {2010},
    arxiv       = {abs/0911.5466},
    abstract    = {We give an example of infinite order rational
  transformation that leaves a linear differential equation covariant. This
  example can be seen as a non-trivial but still simple illustration of an
  exact representation of the renormalization group.},
}