1. Directive 2009/28/EC of the European Parliament and of the Council of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC, https://eur-lex.europa.eu/legal- content/EN/TXT/PDF/?uri=CELEX:32009L0028&from=EN, (accessed January 20, 2024).
2. https://www.epa.gov/laws-regulations/summary-energy-policy-act (accessed January 20, 2024).
3. https://www.iea.org/policies/3080-renewable-energy-law-of-the-peoples-republic-of-china (accessed January 20, 2024).
4. Review on the characteristics of butanol, its production and use as fuel in internal combustion engines
5. Bio-butanol as a new generation of clean alternative fuel for SI (spark ignition) and CI (compression ignition) engines