1. International Civil Aviation Organization. Annual Safety Report 2019https://www.icao.int/safety/Documents/ICAO_SR_2019_29082019.pdf
2. International Civil Aviation Organization. Global Aviation Safety Plan 2020–2022https://www.icao.int/Meetings/anconf13/Documents/Doc_10004_GASP_2020_2022_Edition.pdf
3. Implementation support officer safety, air navigation bureau at ICAOwww.futureairport.com
4. International Air Transport Association. Safety Report 2019https://www.iata.org/en/publications/safety-report/
5. Statistical Summary of Commercial Jet Airplane Accidents-Worldwide Operations 1999–2018http://www.boeing.com/resources/boeingdotcom/company/about_bca/pdf/statsum.pdf