- vk.com wall-163696793_63Торцевые: http://www.tube-tester.com/sites/nixie/trade01-nixie
- twitter.com txsector/status/922219044949786625Source is "Znakosinteziruyushchiye indikatory," N. I. Vukolov & A. N. Mikhailov. Available in DjVu format here: http://tube-tester.com/sites/nixie/dat_arch/russian-book-0001.djvu…