On the recovery of a Pfaffian system of Fuchsian type from the generators of the monodromy group

From relations of the fundamental group $\pi_1(C^n-L)$ the author obtains commutation relations for the coefficient matrices of a Pfaffian system of Fuchsian type in $C^n$, with manifold of singularities on the union of a finite number of hyperplanes $L$. Expansions of the coefficient matrices in powers of the logarithms of the generators of the monodromy group are given under the condition that these matrices are close to the identity.
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