@Article{91581,
     author = "Zbigniew Długosz",
     title = "Migration of population in big Polish cities as compared to smaller cities and towns in the light of selected parameters of the migration process ",
     year =  2006,
     volume =  ,
     number =  6,
     journal =  Bulletin of Geography. Socio-Economic Series,
     pages =  s. 33-50,
    }