Jia-Jun Wang, Guang-Yu Liu, “Hierarchical sliding-mode control of spatial inverted pendulum with heterogeneous comprehensive learning particle swarm optimization”, Information Sciences, 495 (2019), 14
I. Yu. Polekhin, “On the Impossibility of Global Stabilization of the Lagrange Top”, J. Appl. Math. Mech., 53:2 (2018), 71–75