https://files.taxfoundation.org/20221013150933/International-Tax-Competitiveness-Index-2022.pdf
http://ec.europa.eu/budget/mff/hlgor/library/reports-communication/hlgor-report_20170104.pdf
http://visegradinsight.eu/app/uploads/2019/11/EaP-2030-Trends.pdf
https://www.euronews.com/2018/09/26/after-three-decades-and-trillions-in-investment-east-germany-still-trails-west