« The approximate or exact analytical solutions for the differential equations which describe parametric free vibrations of mechanical systems ». 2013. Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XIV, Inginerie mecanică = Annals of “Dunarea de Jos“ University of Galati. Fascicle XIV, Mechanical Engineering 20 (1): 65-68. https://ojs.ugal.ro/index.php/im/article/view/3556.