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

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