Piotr Pruski, Stefan Paszek. “Calculations of Electromechanical Eigenvalues Based on Generating Unit Instantaneous Power and Angular Speed Waveforms at a Step Disturbance”. Acta Energetica, no. 02 (June 30, 2015): 68–77. Accessed September 21, 2025. https://www.actaenergetica.org/index.php/journal/article/view/429.