1. Vorlesungen uber Himmelsmechanik;Siegel,1954
2. “Two Works on Iteration and Related Questions,”;Hadamard;Bull. Amer. Math. Soc.,1944
3. “A New Technique for Proving the Existence of Analytic Functions, Ordinary Differential Equation,”;Diliberto,1972
4. The Theory of Branching Processes;Harris,1963