1. Integral Operators in the Theory of Linear Partial Differential Equations;Bergman,1969
2. Kernel Functions and Elliptic Differential Equations in Mathematical Physics;Bergman,1953
3. The radial heat polynomials and related functions;Bragg;Trans. Amer. Math. Soc.,1965
4. The Solution of Boundary Value Problems by the Method of Integral Operators;Colton,1976
5. Cauchy's problem for a singular partial differential equation;Colton;J. Differential Equations,1970