1. European Commission. Biofuels. in: Secondary European Commission, (Ed.). Secondary Biofuels. Accessed: 20.06.18. https://ec.europa.eu/energy/en/topics/renewable-energy/biofuels.
2. European Commission. Renewable energy. in: Secondary European Commission, (Ed.). Secondary Renewable energy. Accessed: 23.08.18. https://ec.europa.eu/energy/en/topics/renewable-energy.
3. HLPE. Biofuels and food security. A report by the High Level Panel of Experts on Food Security and Nutrition of the Committee on World Food Security. Rome 2013, 2013.
4. European Commission. Renewable energy directive in: Secondary European Commission, (Ed.). Secondary Renewable energy directive Accessed: 31.10.17. https://ec.europa.eu/energy/en/topics/renewable-energy/renewable-energy-directive.
5. Country-level assessment of long-term global bioenergy potential;Deng;Biomass Bioenergy,2015