@book{TorneyPurtaLehmannOswaldetal.2001,
  author    = {Torney-Purta, Judith and Lehmann, Rainer and Oswald, Hans and Schulz, Wolfram},
  title     = {Citizenship and education in twenty-eight countries : civic knowledge at age fourteen},
  publisher = {IEA},
  address   = {Amsterdam},
  isbn      = {90-5166-834-1},
  pages     = {237 S.},
  year      = {2001},
  language  = {en}
}