Ignatjev, V., A. Nikitin, and S. Yushanov. “Measuring the Phase Shifts of Quasi-Harmonic Signals”. Numerical Methods and Programming (Vychislitel’nye Metody I Programmirovanie), vol. 14, no. 38, Oct. 2013, pp. 424-31, https://en.num-meth.ru/index.php/journal/article/view/653.