Text this: Wave manipulation in topological classical-wave systems

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| |  | ||  \ \\/ //  /_   _// | || | || |  __ \\  
| |/\| ||   \ ` //   `-| |,-  | || | || | |  \ || 
|  /\  ||    | ||      | ||   | \\_/ || | |__/ || 
|_// \_||    |_||      |_||    \____//  |_____//  
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