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Searching for Articles
----------------------

`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').