\Bibitem{1} \by I.~L. \paper Ýëåêòðîííî-îïòè÷åñêèé ïèðîìåòð \jour UFN \yr 1950 \vol 42 \issue 3 \pages 498--500 \mathnet{http://mi.mathnet.ru/ufn13594} \crossref{https://doi.org/10.3367/UFNr.0042.195011j.0498}