@Article{484391,
     author = "Mariusz Próchniak, Bartosz Witkowski",
     title = "On the Use of Panel Stationarity Tests in Convergence Analysis : Empirical Evidence for the EU Countries",
     year =  2016,
     volume =  11,
     number =  1,
     journal =  Equilibrium. Quarterly Journal of Economics and Economic Policy,
     pages =  s. 77-96,
    }