SZLÁVIK, János - HORVÁTH, György. Administrative systems in the European Union and in the states of the Visegrád group - reforms in the service of sustainable development. In Acta oeconomica Cassoviensia : scientific journal. - Košice : PHF EU Košice, 2011. ISSN 1337-6020, 2011, roč. 4, č. 1, s. 4-12.