1. Single European Sky ATM Research Joint Undertaking, https://www.sesarju.eu. SESAR Joint Undertaking, n.d.
2. Federal Aviation Administration, https://www.faa.gov/nextgen/, Modernization of U.S. Airspace, n.d.
3. Ministry of Land, Infrastructure, Transport and Tourism, https://www.mlit.go.jp/en/koku/koku_fr13_000000.html, Collaborative Actions for Renovation of Air Traffic Systems (CARATS), n.d.
4. International Civil Aviation Organization, https://www.icao.int/Meetings/a39/Documents/WP/wp_304_en.pdf, China’s Strategy for Modernizing Air Traffic Management, n.d.
5. Eurocontrol, “LINK2000+: ATC data link operational guidance in support of DLS regulation,” No 29/2009, vol. 6, 17 December 2012, online available at https://www.skybrary.aero/bookshelf/books/2383.pdf