Comment by autoexec

Besides just not wanting to look insecure, there are good reasons to include sources, even in cases where you actually have the info memorized.

It shows someone where they can find that information for themselves in the future. That way they don't have to bug you later if they forget and it can give them a useful resource they can explore. If nothing else it demonstrates that at least one other person had the same understanding of something that I did which could be reassuring.