1. Über die numerische Auflösung von Ranswertproblemen bei elliptischen partiellen Differentialgleichungen;Batschelet, Eduard;Z. Angew. Math. Phys.,1952
2. Approximation of derivatives by finite difference methods in elliptic boundary value problems;Bramble, J. H.;Contributions to Differential Equations,1964
3. A finite difference analogue of the Neumann problem for Poisson’s equation;Bramble, J. H.;J. Soc. Indust. Appl. Math. Ser. B Numer. Anal.,1965
4. O. BUNEMAN, A Compact Non-Iterative Poisson Solver, SUIPR Report No. 294, Inst. Plasma Research, Stanford Univ., May 1969, 11 pp.
5. On direct methods for solving Poisson’s equations;Buzbee, B. L.;SIAM J. Numer. Anal.,1970