Upvote:7
I'm having trouble locating it in the 1839 L'Organisation du travail.
The earliest mention I've been able to find is from Louis Blanc 1851 brochure Plus de Girondins on page 92:
De chacun selon ses facultΓ©s, Γ chacun selon ses besoins
This exact phrasing is asserted as being the original one by French Wikipedia article.
A less-trusted, secondary source mentions another secondary source that reportedly attributes a similar phrase to some unspecified 1831 work by Enfantin, see Crisis and the Apocalypse of Man footnote 8 on page 315. But I would expect it to be as far as "from each according to his abilities, to each according to his work", which is quite a different idea.
Enfantin was one of saint-simonians, which might explain why someone would attribute the quote (correctly or incorrectly) to Saint-Simon.