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             ___     _    _      ___      _____   
    ___     / _ \\  | \  / ||   / _ \\   /  ___|| 
   /   ||  / //\ \\ |  \/  ||  / //\ \\ | // __   
  | [] || |  ___  ||| .  . || |  ___  ||| \\_\ || 
   \__ || |_||  |_|||_|\/|_|| |_||  |_|| \____//  
    -|_|| `-`   `-` `-`  `-`  `-`   `-`   `---`   
     `-`

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Text this: Resource allocation in multiuser OFDM based cognitive radio systems