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2. \bysame, Topologie generale, Paris, Hermann, 1942, chaps. 3 and 4.
3. \bysame, Topologie generale, Paris, Hermann 1948, chap. 9.
4. Sur les fonctions multiformes;Brisac, Robert;C. R. Acad. Sci. Paris,1947
5. Convergences;Choquet, G.;Ann. Univ. Grenoble. Sect. Sci. Math. Phys. (N.S.),1948