1. M. Kaminskii, Atomic and Ionic Collisions on a Metal Surface [in Russian], Mir, Moscow (1967).
2. N. V. Pleshivtsev, Cathode Sputtering [in Russian], Atomizdat, Moscow (1968).
3. G. Garter et al., Rad. Res. Rev.,3, No. 1, 1 (1971).
4. M. Steinberg, Adv. Nucl. Sci. Tech.,1, 247 (1962).
5. V. I. Gol'danskii et al., Isotopy v SSSR, No. 12, 7 (1968).