Christina Aguilera 

You Tube is a good source for proof of whistle register singing. Singers have been added back onto the whistle register list because of proof from youtube. Stop spoiling people's fun. Proof is proof no matter where is it from. And don't bring up the subject about deaf people because it has absolutely nothing to do with this. deaf people wouldn't remove people from the whistle register list becaues they are unable to verify, but people who aren't are able to verify, like you. So stop manipulating and vandalising wikipedia. We were all happy until you came along. Leave us alone.