@book{BaumgaertelCarey2000,
  author    = {Baumg{\"a}rtel, Hellmut and Carey, A.},
  title     = {Hilbert systems for actions of the circle group},
  series = {ESI-Preprint / Erwin-Schr{\"o}der-Institut f{\"u}r Mathematische Physik, Wien},
  volume    = {940, 2000},
  journal   = {ESI-Preprint / Erwin-Schr{\"o}der-Institut f{\"u}r Mathematische Physik, Wien},
  publisher = {Erwin-Schr{\"o}der-Institut f{\"u}r Mathematische Physik},
  address   = {Wien},
  pages     = {14 S.},
  year      = {2000},
  language  = {en}
}