I've lost my sources for an individual. Either I never wrote it down or it's been lost by my software (probably the former).
I realized this when I came back to this individual the other day and saw the birth recorded as in Yugoslavia about 1864. For those who know their history, this is a problem. Yugoslavia wasn't formed until post-WWI (1918). My course of action was to review the original source (probably a birth or immigration record). Unfortunately, my sources were not listed and I could not find them. A preliminary search did not uncover anything.
Question:
With a situation like this, what should I do?
Obviously, the best case scenario is to be more careful about recording sources in the first place, but what steps should I take to retrieve my source(s) when something like this does happen?