Is there a way to do this?

I would like to know if this is possible and if so, how do I do it. Say I have a vocal track recorded in a particular session in PT's 9, (Win 7,32 bit), but for what ever reason I delete that version of the session and start over. I know that I can recover it from the backups and every thing is cool except for the vocal. Then I remember,(which is unusual for me), that there was another vocal track in another version that I liked better. Is there a method in Pro tools whereby one can copy and paste or transfer a track from one session to a different session?

Is there a way to do this?