Leopa, A. The Friction Force Dependence at Simple Pendulum Sliders by Relative Speed and Temperature of the Surfaces in Contact. Analele Universităţii "Dunărea de Jos" din Galaţi. Fascicula XIV, Inginerie mecanică = Annals of “Dunarea de Jos“ University of Galati. Fascicle XIV, Mechanical Engineering 2014, 21, 31-34.