@misc{SchmidtSchaussMann2007,
  author    = {Manfred Schmidt-Schauß and Matthias Mann},
  title     = {On equivalences and standardization in a non-deterministic call-by-need lambda calculus},
  booktitle = {Technical report Frank / Johann-Wolfgang-Goethe-Universit{\"a}t, Fachbereich Informatik und Mathematik, Institut f{\"u}r Informatik ; 31},
  number    = {Version: 15 August 2007},
  url       = {http://www.ki.informatik.uni-frankfurt.de/papers/frank/frank31-approxcalc.pdf},
  institution = {Informatik},
  series    = {Technical report Frank / Johann-Wolfgang-Goethe-Universit{\"a}t, Fachbereich Informatik und Mathematik, Institut f{\"u}r Informatik},
  number    = {31},
  type      = {workingpaper},
  pages     = {26},
  year        = {2007},
}