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

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Text this: Angle-selective surface based on multi-layered frequency-selective surfaces