The O'Reilly and Associates book mentioned is now out of print. The
book's author, Jerry Peek, now maintains an online version of this book,
so refer people to that instead. [See the message 'Suggestion: add a
link to your document "An MH Primer"' posted to freebsd-doc on 6th
August 2002]

While I'm here, update a broken link to the MH FAQ.