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  ______   __   __    ______    ______   ______   
 /_   _//  \ \\/ //  /_   _//  /_   _// |      \\ 
 `-| |,-    \ ` //   `-| |,-    -| ||-  |  --  // 
   | ||      | ||      | ||     _| ||_  |  --  \\ 
   |_||      |_||      |_||    /_____// |______// 
   `-`'      `-`'      `-`'    `-----`  `------`

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Text this: Nonlinear refraction in ZnS crystal associated with three-photon absorption