@unpublished{FreedenGutting2008,
  author  = {Willi Freeden and Martin Gutting},
  title   = {On the Completeness and Closure of Vector and Tensor Spherical Harmonics},
  institution = {Fachbereich Mathematik},
  series    = {Schriften zur Funktionalanalysis und Geomathematik},
  number    = {37},
  year    = {2008},
  url  = {http://nbn-resolving.de/urn:nbn:de:hbz:386-kluedo-15199},
}