1. “On the Theory of Age-dependent Stochastic Branching Processes,”;Bellman;Proc. Nat. Acad. Sci. USA,1948
2. The Theory of Branching Processes;Harris,1963
3. Cosmic Rays;Janossy,1950
4. “Diffuse Reflection of Light by a Foggy Medium,”;Ambarzumian;C. R. Acad. Sci., U.R.S.S.,1943
5. V. A. Ambarzumian, et al., Teoreticheskaya Astrofizika, Moscow, 1952.