Characteristic numbers of primary control in the isolated Estonian power systemMedvedeva-Tšernobrivaja, Viktoria; Attikas, Raivo; Tammoja, HeikiOil shale2011 / 1S, p. 214-222 : ill https://www.airitilibrary.com/Article/Detail/17367492-201103-201104080003-201104080003-214-222 On efficiency of optimization in power systemsKeel, Matti; Medvedeva-Tšernobrivaja, Viktoria; Šuvalova, Jelena; Tammoja, Heiki; Valdma, MatiOil shale2011 / 1S, p. 253-261 : ill