@article{MisiurewiczRodriguez2005,
  author    = {{Misiurewicz, Michal and Rodriguez, Ana}},
  title     = {{Real $3X+1$}},
  journal   = {{Proc. Amer. Math. Soc.}},
  year      = {{2005}},
  volume    = {{133}},
  pages     = {{1109--1118}},
  note      = {{MR 2005j:37011}},
}