1. European Commission Decision C(2015)2453 of 17 April 2015.
2. EUROSTAT. (n.d.). Population Database. Retrieved from http://ec.europa.eu/eurostat/web/population-demography-migration-projections/population-data/main-tables.
3. PLEEC - Rudolf Giffinger, G.H. Typology of cities - WP2 - Deliverable 2.2. Vienna: TUWIEN Team;January 2014.
4. Rheinisch-Westfälisches Institut für Wirtschaftsforschung. Second State of European Cities Report. Research Project for the European Commission, DG Regional Policy. Essen, Germany: Policy Research & Consultancy – PRAC; November 2010.
5. EIP-SCC – the Market Place of the European Innovation Partnership on Smart Cities and Communities – EU projects page (https://eu-smartcities.eu/eu-projects).