The lead runner is entitled to the base unless he is forced to advance because of the batter becoming a runner.
Tag the following guy. He's out. Proper mechanic is point repeatedly at the guy who is tagged out and say "You, you're out!".
As for rule references, look 'em up...
MLB -
Official Rules | MLB.com: Official info
NCAA -
NCAA Baseball Central Hub - News and Announcements
JJ