\Bibitem{KanLyu25} \by V.~G.~Kanovei, V.~A.~Lyubetskii \paper Independence of the comprehension schema in second-order arithmetic from the parameter-free countable choice \jour Mat. Zametki \yr 2025 \vol 117 \issue 2 \pages 257--269 \mathnet{http://mi.mathnet.ru/mzm14255} \crossref{https://doi.org/10.4213/mzm14255}