Our - at lleast questionable - old table offers Russia: Red, Grey, Black (L, N, G) as the old color coding. To me it sounds fatally like the old Austrian coding completely mixed up (hot and ground swapped over).
I remember reading somewher, that Russia didn't have any grounded receptacles in residential.
I'd say common sense and a phase probe are the most important thing when dealing with old wiring anywhere.
Back when we had our 127/220V wye system electricians used virtually _any_ color for the 2 hots. I've seen 2 greens, 2 blacks, 2 yellows, 2 reds(!), 2 purples, 2 grays, 2 whites,...
Where cable was used red was liberally used as a phase conductor (e.g. 2 individually switched phases to a light fixture were black and red, or a switched and an unswitched phase). Even 3ph systems can have the weirdest colors. I recently saw a 1957 main fuse box that had various combinations of 4 yellows, 4 whites, 4 purples and IIRC even 4 reds for the individual apartments. So _never_ trust a red wire to be a ground!
