V. E. Adler, “Negative flows for several integrable models”, Journal of Mathematical Physics, 65, no. 2, 2024, 023502
Na Xiong, Sen-Yue Lou, Biao Li, Yong Chen, “Classification of Dark Modified KdV Equation”, Commun. Theor. Phys., 68, no. 1, 2017, 13
I T Habibullin, A R Khakimova, “Discrete exponential type systems on a quad graph, corresponding to the affine Lie algebras $A^{(1)}_{N-1}$”, J. Phys. A: Math. Theor., 52, no. 36, 2019, 365202
P.R. Gordoa, A. Pickering, J.A.D. Wattis, “Solution classes of the matrix second Painlevé hierarchy”, Physica D: Nonlinear Phenomena, 435, 2022, 133295
H. Baran, M. Marvan, “A conjecture concerning nonlocal terms of recursion operators”, J Math Sci, 151, no. 4, 2008, 3083
Yangjie Jia, Shen Wang, Ban Maduojie, “Prolongation structure of supersymmetric nonlinear equation and its Bäcklund transformation”, Journal of Mathematical Physics, 64, no. 6, 2023, 063505
Oleg Morozov, “A recursion operator for the universal hierarchy equation via Cartan’s method of equivalence”, Open Mathematics, 12, no. 2, 2014, 271
Gui-zhang Tu, “Commutator representations and roots of pseudo differential operators”, Acta Math. Appl. Sin. Engl. Ser., 32, no. 3, 2016, 559
Maciej Błaszak, “On the construction of recursion operator and algebra of symmetries for field and lattice systems”, Reports on Mathematical Physics, 48, no. 1-2, 2001, 27
Metin Gürses, Aslı Pekcan, “Nonlocal KdV equations”, Physics Letters A, 384, no. 35, 2020, 126894