http://www.aviationlaw.eu/wp/wp-content/uploads/2013/09/Freedoms-of-the-Air-Explained.pdf
https://onlinelibrary.wiley.com/doi/epdf/10.1111/1467-923X.13172
https://www.brookings.edu/interactives/ukraine-index/?utm_campaign=Brookings%20Brief&utm_medium=email&utm_content=251034578&utm_source=hs_email
https://www.bruegel.org/sites/default/files/2022-10/PC%2018%202022_1.pdf