1. N. Bourbaki, Intégration, Chapter VI, Hermann, Paris, 1963.
2. Pointwise limits for sequences of convolution operators;Edwards, R. E.;Acta Math.,1965
3. A Poisson formula for semi-simple Lie groups;Furstenberg, Harry;Ann. of Math. (2),1963
4. Pure and Applied Mathematics, Vol. XII;Helgason, Sigurđur,1962
5. A Fatou-type theorem for harmonic functions on symmetric spaces;Helgason, S.;Bull. Amer. Math. Soc.,1968