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Searching for Articles
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`M-s'
Search through all subsequent articles for a regexp
(`gnus-summary-search-article-forward').
`M-r'
Search through all previous articles for a regexp
(`gnus-summary-search-article-backward').
`&'
This command will prompt you for a header field, a regular
expression to match on this field, and a command to be executed if
the match is made (`gnus-summary-execute-command').
`M-&'
Perform any operation on all articles that have been marked with
the process mark (`gnus-summary-universal-argument').