@unpublished{KleinRosenberger2012,
  author  = {Markus Klein and Elke Rosenberger},
  title   = {Tunneling for a class of difference operators},
  institution = {Institut f{\"u}r Mathematik},
  series    = {Preprints des Instituts f{\"u}r Mathematik der Universit{\"a}t Potsdam},
  number    = {1 (2012) 5},
  year    = {2012},
}