@misc{MannSchmidtSchauss2006,
  author    = {Matthias Mann and Manfred Schmidt-Schauß},
  title     = {How to prove similarity a precongruence in non-deterministic call-by-need lambda calculi},
  booktitle = {Technical report Frank / Johann-Wolfgang-Goethe-Universit{\"a}t, Fachbereich Informatik und Mathematik, Institut f{\"u}r Informatik ; 22},
  url       = {http://www.ki.informatik.uni-frankfurt.de/papers/mann/pc_sim_ndnd_IB200106.pdf},
  institution = {Informatik},
  series    = {Technical report Frank / Johann-Wolfgang-Goethe-Universit{\"a}t, Fachbereich Informatik und Mathematik, Institut f{\"u}r Informatik},
  number    = {22},
  type      = {workingpaper},
  pages     = {31},
  year        = {2006},
}