More than one person has shown you that Russia admitted to having its troops illegally operating on Ukrainian territory. As for the sham "referendum," the two choices with regard to secession were "yes," and "yes." Sucks to be ignorant, I know, but I suppose it's a Russian thing.
“Sham referendum” LOL!! I have friends living in Crimea, do you?? Practically all Crimean citizens wanted to become part of Russia & are still pissed that it was just HANDED OVER to Ukraine as a “gift. Study some history. Nice try, dude. Yoy haven’t a clue about Crimea ir it’s people.