https://www.esri.ie/system/files/publications/SUSTAT120.pdf
https://www.brusselsdialogue.net/versions/2/wizard/modules/fileManager/downloadDigitalFile.php?url=https%3A%2F%2Fstatic.s123-cdn-static-d.com%2Fuploads%2F3692253%2Fsecure%2Fnormal_60af8dc3abd29.pdf
https://www.dossier.at/dossiers/aktuelles/zu-kuehl-um-wahr-zu-sein/
https://wiiw.ac.at/the-emissions-reduction-potential-for-freight-transport-on-a-high-speed-rail-line-along-the-european-silk-road-dlp-6635.pdf