@article{DowneyFlumGroheWeyer2007,
  author = "Rod Downey and J{\"o}rg Flum and Martin Grohe and Mark Weyer",
  title = "Bounded fixed-parameter tractability and reducibility",
  journal = "Annals of Pure and Applied Logic",
  year = 2007,
  volume = "148",
  pages = "1--19"
}