Brenna, Morris; Dumbrava, Virgil; Foiadelli, Federica; Lazaroiu, George Cristian; Longo, Michela; Sima, Catalina-Alexandra: 'Case studies from selected countries – Romania and Italy' (Energy Engineering, 2018), 'Energy Storage at Different Voltage Levels: Technology, integration, and market aspects', Chap. 8, pp. 199-217, DOI: 10.1049/PBPO111E_ch8
IET Digital Library, https://digital-library.theiet.org/;jsessionid=6r7sd7dnqti1k.x-iet-live-01content/books/10.1049/pbpo111e_ch8