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  ______     ___     _    _    __   __   _    _   
 /_   _//   / _ \\  | |  | ||  \ \\/ // | \  / || 
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 /__//    |_||  |_|||_// \_||    |_||   |_|\/|_|| 
 `--`     `-`   `-` `-`   `-`    `-`'   `-`  `-`

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Text this: Seasonality and dynamic spatial contagion of air pollution in 42 Chinese cities