- Frequency converter for study purposesJoller, Jüri2nd International (13th All-Russian) Conference on Automatic Electric Drive : AED-98 : Uljanovsk, 23.09.-25.09.19981998 / [3] p
- О подготовке электроприводчиков в ЭстонииLaugis, Juhan; Lehtla, Tõnu2nd International (13th All-Russian) Conference on Automatic Electric Drive : AED-98 : Uljanovsk, 23.09.-25.09.19981998 / [3] p