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+Date and Time Conventions
+=========================
+
+This topic document serves to provide guidance on how to format dates and times
+in the OpenStack public REST APIs.
+
+REST API
+--------
+
+* APIs should use ISO 8601 format to return dates and times in resource
+  representations. For more information see [1]_.
+* It is recommended that the Coordinated Universal Time (UTC) is used to avoid
+  differences in time. For more information see [2]_.
+* Clients should also use the ISO 8601 format when providing dates to the
+  server. The API server should be able to parse and interpret any valid
+  ISO 8601 timestamp in any timezone.
+
+.. [1] http://en.wikipedia.org/wiki/ISO_8601
+.. [2] http://en.wikipedia.org/wiki/Coordinated_Universal_Time