 Moreover, ["L","L"] ⊂ "L" since the commutator of holomorphic vector fields annihilating "F" is again a holomorphic vector field annihilating "F".There is a sharp contrast between the theories of embedded CR manifolds (hypersurface and edges of wedges in complex space) and abstract CR manifolds (those given by the complex distribution "L").Many of the formal geometrical features are similar.