https://www.globalwitness.org/documents/20405/Hydrogen_is_too_expensive_-_September_2022.pdf
https://cepr.org/sites/default/files/news/CovidEconomics19.pdf?utm_medium=email&utm_source=govdelivery#Paper2
https://www.irena.org/-/media/Files/IRENA/Agency/Publication/2021/March/IRENA_World_Energy_Transitions_Outlook_2021.pdf