Assuming this is limit, I would usually just call with two limpers in front of you and the specific example of A10s. If you are in middle position there are still multiple others to act behind you and if you raise and they three bet you are screwed, since some of the limpers will fold to two more bets and that reduces the multiway action potential of A10s and you might be beat by the threebetter.

Keep in mind if you raise the limpers will call assuming it is not raised behind you so you will not get anyone out. A10s is just not good enough to justify raising to "build a pot" as it just not a good enough raising hand. People limp UTG with AQ AJ all the time (including me) which would be a disaster for you if a A falls. This is a case where the more passive the table is, the worse you are as the AJ guy will check and call you all the way to the river when a A comes, you'll never find out where you are at until showdown.

Everything depends on the specific table of course, but I would normally limp and sometimes fold this, never raise it in a typical small stakes hold'em game with two limpers in front of you. I just can't see the advantage, you can't even take control of the table as you don't have position after the flop unless everyone behind folds, which isn't assured. If you were on the button it is more of a discussion.

NL it is a completely different situation as you can get people out of the pot,an answer that I am not qualified to give an eduacated answer on. I would be surprised if any LIMIT book said to raise this in middle position with two limpers, was this a NL book?