(Reuters, DPA - 19/02/10; Standart, Dnevnik, Tiskovna agencija Focus, The Banker -16/02/10; Bugarski energetski holding, Državna elektro tvrtka, Državno regulatorno povjerenstvo za energetiku i vode)
(Reuters, DPA - 19/02/10; Standart, Dnevnik, Focus News Agency, The Banker -16/02/10; Bulgarian Energy Holding, National Electric Company, State Energy and Water Regulatory Commission)