The 1891 Census, it states that my ggf was born in Tourburg, Russia. I have scratched my head in vain about Tourburg, and it is quite unclear what place can be meant here. I came across the name 'Yurburg' and thought that 'Tourburg' might be a clerical error for Yurburg. Yurburg (German: Georgenburg) is quite close to Vilkovisk (where his wife was born) so it would make sense if he had come >from there. Can someone shed any light on this?