- Measurement of soil water content by percometerSaue, Triin; Kadaja, Jüri; Plakk, Tiit1st Global Workshop on High Resolution Digital Soil Sensing & Mapping : 5-8 February, Sydney : workshop programm & papers. 12008 / p. 184-192
- Percometer - a capacitive probe instrument for soil dielectric constant and conductivity measurement and monitoringPlakk, TiitInternational Conference on Metrology of Environmental, Food and Nutrional Measurements : 9.-12.09.2008, Budapest, Hungary2008 / p. 17-19