3 citations to https://www.mathnet.ru/eng/dan8099

1. S. I. Svinolupov, V. V. Sokolov, “Factorization of evolution equations”, Russian Math. Surveys, 47:3 (1992), 127–162            
2. V. V. Sokolov, “Pseudosymmetries and differential substitutions”, Funct. Anal. Appl., 22:2 (1988), 121–129          
3. V. V. Sokolov, “On the symmetries of evolution equations”, Russian Math. Surveys, 43:5 (1988), 165–204