[2] https://ec.europa.eu/eurostat/tgm/table.do;jsessionid=ry3zwdU7T9YDQG000MTm5TnfeUfEi-_CC9uYoKPmRIFoLelPAw1r!2143818385?tab=table&plugin=1&language=en&pcode=tec00114Search in Google Scholar
[3] https://data.worldbank.org/indicator/SP.URB.TOTL.IN.ZS?locations=ROEU&name_desc=true&view=chartSearch in Google Scholar
[4] https://data.worldbank.org/indicator/EN.ATM.NOXE.ZG?locations=RO-EU&view=chartSearch in Google Scholar