We establish representations of a monotone mapping as the sum of a maximal subdifferential mapping and a "remainder" monotone mapping, where the remainder is "acyclic" in the sense that it contains no nontrivial subdifferential component. This is the nonlinear analogue of a skew linear operator. Examples of indecomposable and acyclic operators are given. In particular, we present an explicit nonlinear acyclic operator.
SIAM Journal on Optimization Vol. 18, Issue 3, p. 946 - 960