La Défense et illustration de la langue française
La Défense et illustration de la langue française (French pronunciation: [la defɑ̃s e ilystʁɑsjɔ̃ də la lɑ̃ɡ fʁɑ̃sɛːz]; The Defense and Illustration of the French Language) is a literary theory text written during the Renaissance in 1549 by the French poet Joachim du Bellay. It was a manifesto of the ideas of the group originally known as La Brigade, later as La Pléiade.
Source: Wikipedia — La Défense et illustration de la langue française (CC BY-SA 4.0)