Fondements de la Géometrie Algébrique
Fondements de la Géometrie Algébrique (FGA) is a book that collected together seminar notes of Alexander Grothendieck. It is an important source for his pioneering work on scheme theory, which laid foundations for algebraic geometry in its modern technical developments.
Source: Wikipedia — Fondements de la Géometrie Algébrique (CC BY-SA 4.0)