Let X be a complex analytic manifold, D [sub] X a free divisor with jacobian ideal of linear type (for example, a locally quasi-homogeneous free divisor), j: U = X - D rightarrowhook X the corresponding open inclusion, varepsilon an integrable logarithmic connection with respect to D and [L] the local system of the horizontal sections of varepsilon on U. In this paper we prove that the canonical morphisms [IMG]/medium/pdn04301.gif" ALT="Formula "> are isomorphisms in the derived category of sheaves of complex vector spaces for k >> 0 (locally on X). 10.1112/plms/pdn043