Yang, Dechang; Rehtanz, Christian; Li, Yong; Yang, Deyou: 'A hybrid method and its applications to analyse the low frequency oscillations in the interconnected power system', IET Generation, Transmission & Distribution, 2013, 7, (8), p. 874-884, DOI: 10.1049/iet-gtd.2012.0291
IET Digital Library, https://digital-library.theiet.org/;jsessionid=2hddo84go9jke.x-iet-live-01content/journals/10.1049/iet-gtd.2012.0291