\Bibitem{Dom94} \by A.~V.~Domrin \paper Letter to the editor \jour Mat. Zametki \yr 1994 \vol 56 \issue 1 \pages 153 \mathnet{http://mi.mathnet.ru/mzm2236} \mathscinet{https://mathscinet.ams.org/mathscinet-getitem?mr=1309832} \zmath{https://zbmath.org/?q=an:0952.32022} \transl \jour Math. Notes \yr 1994 \vol 56 \issue 1 \pages 759 \crossref{https://doi.org/10.1007/BF02110570}