Oh, those. Well, really your V+ and V- can be at any arbitrary voltage (as long as the reference ground for the opamp is equal to (V+ - V-)/2 so if globally V- is at 0v and V+ is at 16v then "ground" for the opamp needs to be at 8v.) your ground needs to be in between V+ and V-. So what you have there looks like it should work, that simple voltage divider should get ground in between V+ and V-.