MacTutor
29th April
On this day in 1901, Lebesgue published his famous paper Sur une généralisation de l'intégrale définie in the Comptes Rendus of the French Academy of Sciences. In this he gave the definition of the Lebesgue integral that generalises the notion of the Riemann integral by extending the concept of the area below a curve to include many discontinuous functions.
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1952.
The postage stamp of one of today's mathematicians at THIS LINK was issued in 1952.