@article{MAN_1964__155_161193,
     author = {P.L. Butzer and G. SUNOUCHI},
     title = {Approximation {Theorems} for the {Solution} of {Fourier's} {Problem} and {Dirichlet's} {Problem.}},
     journal = {Mathematische Annalen},
     pages = {316--330},
     publisher = {mathdoc},
     volume = {155},
     year = {1964},
     zbl = {0178.12603},
     url = {http://geodesic.mathdoc.fr/item/MAN_1964__155_161193/}
}