@Article{231784,
     author = "Krystian Heffner, Brygida Solga",
     title = "Factors shaping the economic migrations after accession of Poland to the European Union ",
     year =  2004,
     volume =  ,
     number =  3,
     journal =  Bulletin of Geography. Socio-Economic Series,
     pages =  s. 115-123,
    }