Application of the Lie symmetry approach to an extended Jimbo–Miwa equation in (3+1) dimensions Sachin Kumar, Vishakha Jadaun and Wen-Xiu Ma Eur. Phys. J. Plus, 136 8 (2021) 843 Published online: 15 August 2021 DOI: 10.1140/epjp/s13360-021-01813-1