1. European Commission (2015a) A framework strategy for a resilient energy union with a forward-looking climate change policy. Report
2. European Commission (2015b) Communication on the state of the energy union. Report
3. European Commission (2017a) Second report on the state of the energy union. Report
4. European Commission (2017b) Third report on the state of the energy union. Report
5. European Commission (2019) Fourth report on the state of the energy union. Report