• Synchronous sampling and demodulation in an instrument for multifrequency bioimpedance measurementMin, Mart; Parve, Toomas; Ronk, Ants; Annus, Paul; Paavle, ToivoIEEE transactions on instrumentation and measurement2007 / 4, p. 1365-1372 : ill https://ieeexplore.ieee.org/document/4277035