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

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