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by M. Marvan
Preprints: GA 3/2003 and DIPS 03/2003 and nlin.SI/0306006
We present a criterion of reducibility of a zero curvature representation to a solvable subalgebra, hence to a chain of conservation laws. Namely, we show that reducibility is equivalent to the existence of a section of the generalized Riccati covering. Results are applied to conversion between Guthrie's and Olver's form of recursion operators. include "konec.inc"; ?>