SamoilenkoV. G. “Integrability of Nonlinear Dynamical Systems and Differential Geometry Structures”. Ukrains’kyi Matematychnyi Zhurnal 45, no. 3 (March 25, 1993): 419–427. Accessed October 6, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/5824.