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3. [3] M. Brelot, Sur un theoremede nonexistence relatif a Vequation u=c (M)u, Bull. Sci. Math., 56 (1932), 389-395.
4. [4] M. Brelot, Etude a la frontiere de la solution du probleme de Dirichlet generalise relatif a Vequation u =cu+f; c(M)^0, \f{M) borne, Rend. 1st. Lombardo, 65 (1932),119-128.
5. [5] M. Brelot, Sur Failure a lafrontiere des integrates bornesde u = c (M)u(c^O), Ibid., 433-448.