[1]
V. V. Yevstafyeva, “Existence of two-point oscillatory solutions of a relay nonautonomous system with a multiple eigenvalue of a real symmetric matrix”,
Ukr. Mat. Zhurn.
, vol. 73, no. 5, pp. 640–650, May 2021, doi:
10.37863/umzh.v73i5.6379
.