@unpublished{NazaikinskiiSternin2008,
  author  = {Vladimir Nazaikinskii and Boris Sternin},
  title   = {Relative elliptic theory},
  institution = {Institut f{\"u}r Mathematik},
  series    = {Preprint},
  number    = {(2002) 23},
  year    = {2008},
}