[1] Web Services Internationalization (WS-I18N) (2008-07-16 01:06:50 +09:00 版) https://www.w3.org/International/core/ws-i18n/ws-i18n#sec-collation

The optional i18n:collation element information item MAY appear at most one time in the children property of the i18n:preferences element information item.
(01) i18n:collation(collation identifier based on
(02) the IANA Collation Registry</i18n:collation>
The i18n:collation element information item represents the collation used in the web services operation. Its value MUST be a valid [IANA Collation Registry] collation identifier.