Audin, Michèle Cartan, Lebesgue, de Rham and the analysis situs in the 1920s. Scenes of the Parisian life. (Cartan, Lebesgue, de Rham et l’analysis situs dans les années 1920. Scènes de la vie parisienne.) (French) Zbl 1270.01012 Gaz. Math., Soc. Math. Fr. 134, 49-75 (2012). This paper deals with mathematicians (Lebesgue, Cartan, Poincaré, Alexandroff, Hopf, “Bourbaki” (as seen through the eyes of G. de Rham)) and their mathematics. De Rham wrote a survey of these important days and work in Paris in the 1920s, on topology, domain invariance, open sets, work of Brouwer, Blumenthal, and many others, the “Seminaire Hadamard”, etc. The whole paper is written like the journey of de Rham through Paris meeting the corresponding persons and their mathematics. A highly original endeavour! So, read the article. An important source is G. de Rham’s paper [“Quelques souvenirs des années 1925–1950”, Cah. Semin. Hist. Math. 1980, No. 1, 19–36 (1980; Zbl 0449.01003)]; the paper under review might be considered as a work-out of that paper, with up-to-date material added. It makes everything highly readable. Reviewer: R. W. van der Waall (Huizen) MSC: 01A60 History of mathematics in the 20th century 01A72 Schools of mathematics 01A70 Biographies, obituaries, personalia, bibliographies 54-03 History of general topology 55-03 History of algebraic topology 58A12 de Rham theory in global analysis 58-03 History of global analysis Keywords:topology; homotopy; homology; history of mathematics in Paris; de Rham’s historical ramblings; analysis situs Citations:Zbl 0449.01003 PDF BibTeX XML Cite \textit{M. Audin}, Gaz. Math., Soc. Math. Fr. 134, 49--75 (2012; Zbl 1270.01012) OpenURL