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

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Text this: On subgroups of crystallographic Coxeter groups