BrzychczyS., PrykarpatskyA. K., and SamoilenkoV. G. “Finite-Dimensional Reductions of Conservative Dynamical Systems and Numerical Analysis. I”. Ukrains’kyi Matematychnyi Zhurnal 53, no. 2 (February 25, 2001): 220-228. Accessed November 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4237.