2 citations to https://www.mathnet.ru/eng/intf96

1. M. V. Shamolin, “Examples of integrable equations of motion of a five-dimensional rigid body in the presence of internal and external force fields”, J. Math. Sci. (N. Y.), 287:5 (2025), 767–803        
2. E. M. Chirka, “Rimanovy poverkhnosti”, Lekts. kursy NOTs, 1, MIAN, M., 2006, 3–105