V. V. Kozlov, “Instability of Equilibria in a Solenoidal Force Field”, Math. Notes, 113:2 (2023), 220–227
Valery V. Kozlov, “Formal Stability, Stability for Most Initial Conditions and Diffusion in Analytic Systems of Differential Equations”, Regul. Chaotic Dyn., 28:3 (2023), 251–264
V. V. Kozlov, “On Instability in Systems with an Integral Invariant”, Diff Equat, 58:10 (2022), 1427
V. V. Kozlov, “First integrals and asymptotic trajectories”, Sb. Math., 211:1 (2020), 29–54
V. P. Palamodov, “On inversion of the Lagrange–Dirichlet theorem and instability of conservative systems”, Russian Math. Surveys, 75:3 (2020), 495–508