Probably a misspelling of "Author", which isn't a standard HTTP Header anyway.
No known client software care about this header; anyway, it is pretty useless other than misspelled.
NOTE: this header may be sent directly by the server software or from some third party application running on that server.
HTTP/1.1 200 OK
Content-Type: text/html; charset=UTF-8
Content-Length: 1903
Auther: Steven Wu
Date: Fri, 30 Jul 2010 16:59:00 +0000
<!DOCTYPE html PUBLIC "-//W3C//DTD ...
...
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