@Article{336723,
     author = "Stefania Środa-Murawska, Daniela Szymańska",
     title = "The concentration of the creative sector firms as a potential basis for the formation of creative clusters in Poland ",
     year =  2013,
     volume =  ,
     number =  20,
     journal =  Bulletin of Geography. Socio-Economic Series,
     pages =  s. 85-93,
    }