P. KRZYWORZEKA and W. CIOCH, “Demodulation of non-stationary machine vibration using cycle-time scale”, Arch. Acoust., vol. 31, no. 2, pp. 167–177, Jun. 2006, Accessed: Apr. 18, 2026. [Online]. Available: http://acoustics.ippt.gov.pl/index.php/aa/article/view/666