R. Schmid et al., A finite dimensional completely integrable system associated with the WKI-and Heisenberg hierarchies, J NONL M PH, 8, 2001, pp. 261-265
We consider the following spectral problem
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where u, v, w are smooth functions. It produces a hierarchy of evolution eq
uations with an arbitrary function A(m-1). This hierarchy includes the WKI
[8] and Heisenberg [7] hierarchies by properly selecting the special functi
on A(m-1). We derive this new evolution equations, and give the finite dime
nsional completely integrable systems (FDCIS) associated with theses equati
ons.