Éléments de mathématique (English: Elements of Mathematics) is a series of mathematics books written by the pseudonymous French collective Nicolas Bourbaki. Begun in 1939, the series has been published in several volumes, and remains in progress. The series is noted as a large-scale, self-contained, formal treatment of mathematics.The members of the Bourbaki group originally intended the work as a textbook on analysis, with the working title Traité d'analyse (Treatise on Analysis). While planning the structure of the work they became more ambitious, expanding its scope to cover several branches of modern mathematics. Once the plan of the work was expanded to treat other fields in depth, the title Éléments de mathématique was adopted. Topics treated in the series include set theory, abstract algebra, topology, analysis, Lie groups and Lie algebras. The unusual singular "mathématique" (mathematic) of the title is deliberate, meant to convey the authors' belief in the unity of mathematics. A companion volume, Éléments d'histoire des mathématiques (Elements of the History of Mathematics), collects and reproduces several of the historical notes that previously appeared in the work. Source: Wikipedia (en)