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2. ISGAN Annex 6 Power T&D Systems, Flexibility needs in the future power system - Discussion paper, 2019. https://www.doi.org/10.13140/RG.2.2.22580.71047.
3. CEDEC, EDSO for smart grids, eurelectric, GEODE, flexibility in the energy transition – a toolbox for electricity DSOs, (2018). https://www.edsoforsmartgrids.eu/wp-content/uploads/Flexibility-in-the-energy-transition-A-tool-for-electricity-DSOs-2018-HD.pdf.
4. Smart Grids Task Force - Expert Group 3, Regulatory Recommendations for the Deployment of Flexibility, Brussels, 2015. https://ec.europa.eu/energy/sites/ener/files/documents/EG3%20Final%20-%20January%202015.pdf.
5. Flexibility and Aggregation – Requirements for their interaction in the market,2014