Goran Frehse Bruce H. Krogh Rob A. Rutenbar Oded Maler Time Domain Verification of Oscillator Circuit Properties. 9-22 2006 153 Electr. Notes Theor. Comput. Sci. 3 http://dx.doi.org/10.1016/j.entcs.2006.02.019 db/journals/entcs/entcs153.html#FrehseKRM06