@misc{Siekmann2006,
  author    = {Helmut Siekmann},
  title     = {The burden of an ageing society as a public debt},
  booktitle = {Working paper series / Institute for Monetary and Financial Stability ; 1},
  url       = {http://www.imfs-frankfurt.de/fileadmin/user_upload/pdf/Working\%20Paper_2006-01.pdf},
  institution = {Institute for Monetary and Financial Stability (IMFS)},
  series    = {Working paper series / Institute for Monetary and Financial Stability},
  number    = {1},
  type      = {workingpaper},
  year        = {2006},
}