E. AUGUSTYN, M. S. KOZIEŃ, and M. PRĄCIK, “FEM Analysis of Active Reduction of Torsional Vibrations of Clamped-Free Beam by Piezoelectric Elements for Separated Modes”, Arch. Acoust., vol. 39, no. 4, pp. 639–644, Dec. 2014, doi: 10.2478/aoa-2014-0069.