@incollection{Hansohm1984,
  author    = {J{\"u}rgen Hansohm},
  title     = {Principal components of variables with different information levels},
  booktitle = {Contributions to operations research and mathematical economics},
  editor    = {Gerald Hammer and Diethard Pallaschke},
  isbn      = {978-3-445-02382-7},
  year      = {1984},
}