VitrychenkoI. E. (1997) “Critical cases of stability of one nonautonomous essentially nonlinear equation of the <em class="a-plus-plus">n</em&gt;th order”, Ukrains’kyi Matematychnyi Zhurnal, 49(5), pp. 720–724. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/5054 (Accessed: 24November2024).