Blaabjerg, Frede; Zhou, Keliang; Wang, Danwei; Yang, Yongheng: 'Periodic Control of Power Electronic Converters' (Energy Engineering, 2016) DOI: 
IET Digital Library, https://digital-library.theiet.org/;jsessionid=8pp924g2o5tkp.x-iet-live-01content/books/po/pbpo082e