https://mailarchive.ietf.org/arch/msg/vpim/wvatEDp_oTDMq8ces5AXACJ_URQ/
https://mailarchive.ietf.org/arch/msg/vpim/EUN8wwwH5RWgk8FEbmyKLA0FAAc/
https://mailarchive.ietf.org/arch/msg/vpim/OmuDTxZlDsxu6zVI5cfJwEcC5a0/
https://mailarchive.ietf.org/arch/msg/vpim/NgPjyow2jN0YHcGGliUc6XagCzo/
https://mailarchive.ietf.org/arch/msg/vpim/SqKy6G98CwK_jpX82mlAapY6_98/
https://mailarchive.ietf.org/arch/msg/vpim/yJhCUx1I5iu_KmGbimiMtrQzCeE/