2 papers
nlin.SI2026
On a class of 3D second-order integrable Lagrangians and their dispersive deformations
Lingling Xue, E. V. Ferapontov, M. V. Pavlov
We investigate integrability of Euler-Lagrange equations associated with 3D second-order Lagrangians of the form \begin{equation*} \int f(u_{xy},u_{xt},u_{yt})\ \text{d}x\text{d}y\…
nlin.SI2026
Lagrangian formulation of the Darboux system
Lingling Xue, E. V. Ferapontov, M. V. Pavlov
The classical Darboux system governing rotation coefficients of three-dimensional metrics of diagonal curvature possesses an equivalent formulation as a sixth-order PDE for a scala…