N. Drăgan, Modal damping ratio calculation for finited of mechanical systems with viscous elastic bearings using virtual instrumentation, Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XIV, Inginerie mecanică = Annals of “Dunarea de Jos“ University of Galati. Fascicle XIV, Mechanical Engineering, vol. 18, nᵒ 1, p. 17-22, juin 2011.