Sullivan minimal-model classification

For simply connected rational spaces of finite type, isomorphic minimal Sullivan models are equivalent to the same rational homotopy type. A quasi-isomorphism between minimal models is an isomorphism, so a zigzag of cochain quasi-isomorphisms produces the same minimal model. Existence and uniqueness come from adjoining closed generators to represent missing cohomology and generators with prescribed decomposable differential to kill kernel classes, degree by degree.