Kostyantyn Zheltukhin, Natalya Zheltukhina, “Semi-discrete hyperbolic equations admitting five dimensional characteristic x-ring”, JNMP, 23, № 3, 2021, 351
Ismagil Habibullin, “Characteristic Lie rings, finitely-generated modules and integrability conditions for (2 + 1)-dimensional lattices”, Phys. Scr., 87, № 6, 2013, 065005
Kostyantyn V Zheltukhin, Natal'ya Aleksandrovna Zheltukhina, “On discretization of Darboux Integrable Systems admitting second-order integrals”, Ufimsk. Mat. Zh., 13, № 2, 2021, 170
Rustem N Garifullin, Elena V Gudkova, Ismagil T Habibullin, “Method for searching higher symmetries for quad-graph equations”, J. Phys. A: Math. Theor., 44, № 32, 2011, 325202