On certain isochronous nonlinear system / *V. M. Budanov.* // Vestnik Moskovskogo Universiteta. Seriya 1. Matematika. Mekhanika. 2013. № 6. P. 59-63
[Moscow Univ. Math. Bulletin. Vol. 72, N 2, 2017. P. 0].

A system of nonlinear ordinal differential equations of second order is considered. It is shown analytically that the solutions of this system are isochronous, which is not characteristic for nonlinear systems. It is also shown that the periodic delta-function is a limiting case for the solution if the amplitude tends to infinity.

*Key words*:
nonlinear system, isochronous oscillations.