First off, I suppose they should be called "versions." I did a minor clean up for the 1998 version, a deep cleaning for the Borderlands edition. Don't trust "look inside." I'm sure they use their old scans.
As for US editions, the first was Whispers, the 1st pb was Berkley which then moved it over to its Jove imprint. Then there have been 3 or 4 Tor editions (I've lost count)
FPW
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