@unpublished{AbedSchulze2009,
  author  = {Jamil Abed and Bert-Wolfgang Schulze},
  title   = {Operators with corner-degenerate symbols},
  institution = {Institut f{\"u}r Mathematik},
  series    = {Preprint},
  number    = {(2008) 01},
  year    = {2009},
}