Search for: [References = "4. Korcelli P., 1977. An approach to the analysis of functional urban regions\: A case study of Poland. IIASA Research Memorandum RM\-77\-052, Laxenburg, http\:\/\/www.iiasa.ac.at\/publication\/more_RM\-77\-052.php \[19 September 2013\]."]