
http://oegfe.at/wordpress/2017/05/the-free-movement-of-workers-within-the-eu-and-the-case-of-austria-balancing-distortions-and-adding-value-op-ed-paul-schmidt-the-european-financial-review/

https://www.unfpa.org/data/world-population-dashboard

https://ec.europa.eu/commission/publications/position-paper-essential-principles-citizens-rights_en