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

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Text this: Optical studies of topological insulator Bi1:5 Sb0:5 Te1:8 Se1:2 using terahertz time-domain spectroscopy.