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__    __     ___      _____    _    _     _  __  
\ \\ / //   / _ \\   |__  //  | || | ||  | |/ // 
 \ \/ //   / //\ \\    / //   | || | ||  | ' //  
  \  //   |  ___  ||  / //__  | \\_/ ||  | . \\  
   \//    |_||  |_|| /_____||  \____//   |_|\_\\ 
    `     `-`   `-`  `-----`    `---`    `-` --`

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Text this: Normal algebraic surfaces with trivial tricanonical divisors