Slow-speed ring-shaped permanent magnet generator for wind applicationsKallaste, Ants; Vaimann, Toomas; Pabut, Ott11th International Symposium "Topical Problems in the Field of Electrical and Power Engineering." Doctoral School of Energy and Geotechnology II : Pärnu, Estonia, January 16-21, 20122012 / p. 66-69 : ill