Compile errors: can't find protocol declaration
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I'm trying to learn Objective-C from a book, and ran into the following errors while trying to work through an exercise in Xcode (arrow indicates place of issue). 

    #import <UIKit/UIKit.h>
    #import "FlashCard.h"
    #import "CreateCardViewController.h"

    --> @interface FlashCardsViewController : UIViewController <CreateCardDelegate> {

The above code results in the error: "Cannot find protocol declaration for 'CreateCardDelegate'. But I am importing "CreateCardViewController.h" where I have declared: 
    @property (nonatomic, assign) id<CreateCardDelegate> cardDelegate;
so don't know what the issue is... 

Having browsed a few post I suspect it may it be due to a #import loop? but if that is the case then I'm not sure how to rectify this error. If you have any suggestions then please explain and do keep in mind that I am a noob.  
