@Article{benamram03,
  author =       "A. Ben-Amram",
  year =         "2003",
  title =        "Tighter Constant-Factor Time Hierarchies",
  journal =      "Information Processing Letters",
  volume =       "87",
  number =       "1",
  pages =        "37--44",
  keywords =     "time complexity, hierarchy theorem, universal
                 program",
  summary =      "For certain computational models, and ``nice'' time bounds
                 T(n), there are problems which can be decided in time
		 (1+\epsilon)T(n) but not in time T(n)."
}