This paper extends derivative-order geometry to the Sato–Grassmannian context. It defines Baker–Akhiezer wave ladders and bispectral closures on the derivative-order axis, deriving two-axis cube laws and bispectral closure conditions for wave and spectral ladders. The work proves that derivative-order ladders admit finite dressing recovery, establishing exact recovery of packets from a finite number of derivative-order layers.
Mohammad Abu-Ghuwaleh (2026) studied this question.