@book{CalinChang2004,
  author    = {Calin, Ovidium and Chang, Der-Chen},
  title     = {The Geometry on a Step 3 Grushin Model},
  series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  journal   = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Mathematik, Arbeitsgruppe Partiell},
  publisher = {Univ.},
  address   = {Potsdam},
  issn      = {1437-739X},
  pages     = {22 S.},
  year      = {2004},
  language  = {en}
}