@TechReport{iza:izadps:dp9020,
            	author={Schmidheiny, Kurt and Suedekum, Jens},
            	title={The Pan-European Population Distribution Across Consistently Defined Functional Urban Areas},
            	year={2015},
	month={Apr},
            	institution={Institute of Labor Economics (IZA)},
            	address={Bonn},
            	type={IZA Discussion Paper},
            	number={9020},
            	url={https://www.iza.org/index.php/publications/dp9020},
	abstract={We analyze the first data set on consistently defined functional urban areas in Europe and compare the European to the US urban system. City sizes in Europe do not follow a power law: the largest cities are "too small" to follow Zipf's law.},
	keywords={urban systems;city size distributions;Zipf's law;functional urban areas},
            }