1. 1. ACEA report: Vehicles in use Europe 2018.
2. 2. AFC TCP: Survey on the Number of Fuell Cell Electric Vehicles, Hydrogen Refuelling Stations and Targets, provided to IEA by AFC TCP, 2018.
3. 3. E4tech: The Fuel Cell Industry Review 2018.
4. 4. E4tech: The Fuel Cell Industry Review 2019.
5. 5. FuelsEurope: Statistical Report 2018.