Title: Quasi-commutative differential graded algebras and homotopy types.

Abstract : A quasi-commutative differential graded algebras (DGA) is given
by a submodule of the tensor product of the algebra by itself, which is
quasi-isomorphic to it, and on which the product is commutative (in the
graded sense). This submodule satisfies some simple axioms. We define now a
functor which associates to a finite CW-complex X a quasi-commutative DGA
of "differential forms" D(X), which is faithful on the level of homotopy
types. In particular, we show how one can extract the Steenrod operations
on the cohomology groups of X and even the homotopy groups of X from this
new algebraic structure.