High-performance differential VCO based on Armstrong oscillator topology. - Nikolay T. Tchamov; Tero Niemi; Niko Mikkola (IEEE J. Solid State Circuits, 2001)

A 1.2-V RF front-end with on-chip VCO for PCS 1900 direct conversion receiver in 0.13-μm CMOS. - Pete Sivonen; Jussi Tervaluoto; Niko Mikkola; Aarno Pärssinen (IEEE J. Solid State Circuits, 2006)

VCO Design With On-Chip Calibration System. - Paavo Väänänen; Niko Mikkola; Petri Heliö (IEEE Trans. Circuits Syst. I Regul. Pap., 2006)