In order to access certain premium libraries such as The Gap Premium you'll need to enter an access (or coupon) code.
If you don't already have the access code please speak to your rep and they will provide it to you.
Once you have the access code go to the Content Library page in Settings or click here.
Now, enter the access code and press the Submit button.
Your new library will be unlocked and you'll be able to view it in the Content Library.