S. Ya. Startsev, “Symmetry Drivers and Formal Integrals of Hyperbolic Systems”, J Math Sci, 252, № 2, 2021, 232
I T Habibullin, A R Khakimova, M N Poptsova, “On a method for constructing the Lax pairs for nonlinear integrable equations”, J. Phys. A: Math. Theor., 49, № 3, 2016, 035202
S. Ya. Startsev, “Differential substitutions of the miura transformation type”, Theor Math Phys, 116, № 3, 1998, 1001
Martin Juráš, Ian M. Anderson, “Generalized Laplace invariants and the method of Darboux”, Duke Math. J., 89, № 2, 1997
Kostyantyn Zheltukhin, Natalya Zheltukhina, “Semi-discrete hyperbolic equations admitting five dimensional characteristic x-ring”, JNMP, 23, № 3, 2021, 351
Handbook of Nonlinear Partial Differential Equations, Second Edition, 2011, 1795
S Ya Startsev, “Relationships between symmetries depending on arbitrary functions and integrals of discrete equations”, J. Phys. A: Math. Theor., 50, № 50, 2017, 50LT01
Peter J. Olver, 3519, Computer Algebra and Geometric Algebra with Applications, 2005, 105
Сергей Петрович Царев, Sergey Petrovich Tsarev, “Факторизация линейных дифференциальных операторов с частными производными и метод Дарбу интегрирования нелинейных уравнений с частными производными”, ТМФ, 122, № 1, 2000, 144
Ian M. Anderson, Niky Kamran, “The variational bicomplex for hyperbolic second-order scalar partial differential equations in the plane”, Duke Math. J., 87, № 2, 1997