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  ______     ___      _  __   _    _     ____    
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   | ||    | / \ ||  | ' //  | || | ||  | |_| || 
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 /__//      \___//   |_|\_\\  \____//   |_|\_\\  
 `--`       `---`    `-` --`   `---`    `-` --`

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Text this: Cooperate-and-access spectrum sharing with ARQ-based primary systems