[1] R. Abounasr, A. Belhaj, J. Rasmussen and E. H. Saidi, Superstring theory on pp waves with ADE geometries, J. Phys. A, 39 (2006) 2797–2841.
[2] R. Bakhshandeh-Chamazkoti and M. Alipour, Lie symmetry classification and numerical analysis of KdV equation with power-law nonlinearity, Math. Rep. (Bucur.), 22 (2020) 163–176.
[3] A. Bejancu and H. R. Faran, Foliations and Geometric Structures, Mathematics and Its Applications (Springer), 580, Springer, Dordrecht, 2006.
[4] G. W. Bluman and J. D. Cole, The general similarity solution of the heat equation, J. Math. Mech., 18 (1969) 1025–1042.
[5] G. W. Bluman and S. Kumei, Symmetry and Differential Equations, Applied Mathematical Sciences, No. 81, Spriger-Verlag, New York, 1989.
[6] M. Brozos-Vázquez, E. García-Río, P. Gilkey, S. Nikvčević and R. Vázques-Lorenzo, The geometry of Walker manifolds, A Publication in the Morgan and Claypool Publishers series, 2009.
[7] M. Chaichi, E. García-Río and Y. Matsushita, Curvature properties of four-dimensional Walker metrics, Classical Quantum Gravity, 22 (2005) 559–577.
[8] P. Giblin, Obituary: Arthur Geoffrey Walker 1909-2001, Bull. London Math. Soc., 36 (2004) 271–280.
[9] P. Gilkey, The geometry of curvature homogeneous pseudo-Riemannian manifolds, ICP Advanced Texts in Mathematics, Imperial College Press, London, 2007.
[10] M. Jafari, A. Zaeim and M. Gandom, On similarity reductions and conservation laws of the two non-linearity terms Benjamin-Bona-Mahoney equation, Journal of Mathematical Extension, 17 (2023) 1–22.
[11] M. Jafari, A. Zaeim and A. Tanhaeivash, Symmetry group analysis and conservation laws of the potential modified KdV equation using the scaling method, Int. J. Geom. Methods Mod. Phys., 19 (2022) 14 pp.
[12] M. Khorshidi, M. Nadjafikhah, H. Jafari and M. Al Qurashi, Reductions and conservation laws for BBM and modified BBM equations, Open Math., 14 (2016) 1138–1148.
[13] S. Lie, On integration of a class of linear partial differential equations by means of definite integrals, Arch. Math., 6 (1881) 328–368, translation by N. H. Ibragimov.
[14] P. J. Olver, Applications of Lie Groups to Differential Equations, Second Edition, Graduate Texts in Mathematics, 107, Springer-Verlag, New York, 1993.
[15] P. J. Olver, Equivalence, invariants and symmetry, Cambridge University Press, Cambridge, 1995.
[16] L. V. Ovsiannikov, Group analysis of differential equations, Academic Press, New York, 1982.
[17] A. A. Shaikh, Y. H. Kim and S. K. Hui, On Lorentzian quasi-Einstein manifolds, J. Korean Math. Soc., 48 (2011) 669–689.
[18] A. G. Walker, Canonical form for a Riemannian space with a parallel field of null planes, Quart. J. Math. Oxford Ser. (2), 1 (1950) 69–79.
[19] A. G. Walker, On parallel fields of partially null vector spaces, Quart. J. Math. Oxford Ser., 20 (1949) 135–145.
[20] ا. زعیم، ی. آریانژاد و م. قیطاسی، پیرامون برخی خمینههای همدیس اینشتین از بعد چهار، ریاضی و جامعه، 7 (2) (1401) 19--36.