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2. http://datacube.statistics.sk/TM1WebSK/TM1WebLogin.aspx.
3. http://appsso.eurostat.ec.europa.eu/nui/show.do?dataset=nama_10_pc&lang=en.
4. http://datacube.statistics.sk/TM1WebSK/.
5. http://www.telecom.gov.sk/files/statistika_vud/preprava_nakl.htm#k4.