I'm a citizen and I'm planning on inviting my mother who lives in Ukraine to visit me for a few months (the problem is that we are not sure whether she'll stay till the end of the visa date or whether she'll have to leave earlier).
May be you can help me : will she be able to exit Ukraine and enter the US without the return ticket (as we are pondering on buying one later, when she's already here), or there's some kind of rule that requires both-ways tickets?
Perhaps you can recommend where I can find such information. Thank you!