1. Effects of Novel Coronavirus (COVID-19) on Civil Aviation: Economic Impact Analysishttps://www.icao.int/sustainability/Pages/Economic-Impacts-of-COVID-19.aspx
2. Commercial Market Outlook 2021–2040https://www.boeing.com/commercial/market/commercial-market-outlook/
3. Airbus Global Market Forecast 2021–2040https://www.airbus.com/en/products-services/commercial-aircraft/market/global-market-forecast
4. Turboprop Market Forecast 2018–2037https://perma.cc/X4VZ-JKW8