https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:52022PC0457&from=EN
https://www.sipri.org/sites/default/files/2025-03/fs_2503_at_2024_0.pdf
https://cerre.eu/wp-content/uploads/2023/06/CERRE_Future-of-Rail-Report_06.06.2023.pdf
https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwiYtOnpoqT1AhXV7rsIHfpxDhcQFnoECAcQAQ&url=https%3A%2F%2Fosf.io%2Fpreprints%2Fsocarxiv%2F8nzb4%2Fdownload&usg=AOvVaw1M87IVrQbHicDueJuLi74b