Apparently the archive server has not recorded all mails sent by the list after:
"Last message date: Wed Nov 27 2013 - 09:21:15 CST" http://www.unicode.org/mail-arch/unicode-ml/y2013-m11/ and before: "Tue Dec 03 2013 - 08:28:01 CST" http://www.unicode.org/mail-arch/unicode-ml/y2013-m12/
