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

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Text this: Vertical directivity of train noise