I am pretty confident that the entire file has been double encoded.

Due to a special relationship between iso-latin-1 and UTF-8, it's not really possible to double-encode.

• encode('iso-latin-1', encode('UTF-8', $text))
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  produces the same output as

  encode('UTF-8', $text)
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• For the characters where it works,

  encode('UTF-8', encode('iso-latin-1', $text))
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  produces the same output as

  encode('UTF-8', $text)
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  For the characters where it doesn't, you'll get a question mark ("?").

• encode('iso-latin-1', encode('iso-latin-1', $text))
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  produces the same output as

  encode('iso-latin-1', $text)
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• The only combination where double-encoding is possible when using those encodings is

  encode('UTF-8', encode('UTF-8', $text))
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