@unpublished{BoeckmannSarkoezi2007,
  author  = {Christine B{\"o}ckmann and Janos Sark{\"o}zi},
  title   = {The ill-posed inversion of multiwavelength lidar data by a hybrid method of variable projection},
  institution = {Institut f{\"u}r Mathematik},
  series    = {NLD Preprints},
  number    = {53},
  year    = {2007},
}