M. A. Zabolotnyi, Yu. M. Barabash, O. P. Dmitrenko, N. P. Kulish, N. A. Davidenko, S. L. Studzinsky, A. P. Olasyuk, A. V. Demchenko, “On the mechanisms of photogeneration of charge carriers in PEPC–C$_{60}$ composites”, Fizika Tverdogo Tela, 55:8 (2013), 1626–1632; Phys. Solid State, 55:8 (2013), 1739–1746
