1. V. A. Ambartsumyan, ?On the fluctuation of the brightness of the Milky Way,? Dokl. Akad. Nauk SSSR,44, 223?226 (1944).
2. D. P. Gaver, Jr., ?An absorption probability problem,? J. Math. Anal, and Appl.,9, No. 3, 384?393 (1964).
3. G. Sh. Lev, ?Semi-Markov processes of multiplications,? Teor. Veroyatn. Ee Primen.,17, No. 1, 160?166 (1972).
4. A. K. Grintsevichus, ?On the continuity of the distribution of a sum of dependent variables connected with independent walks on lines,? Teor. Veroyatn. Ee Primen.,19, No. 1, 163?168 (1974).
5. V. L. Rvachev and V. A. Rvachev, ?On a function with bounded support? [in Ukrainian], Dopov. Akad. Nauk URSR, No. 8, 705?707 (1971).