IBOutlet declarations?

Question

I have seen the code below written 3 different ways (with regards to IBOutlet) Does it matter, I would say adding IBOutlet to both the declaration and the @property was more con

Answer 1

I also found this way (without any property declaration):

@class SwitchViewController;

@interface iPhone_switcherAppDelegate : NSObject  {
    IBOutlet UIWindow *window;
    IBOutlet SwitchViewController *switchViewController;
}

@end

What about this?