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The AsOfDateTime is the latest date/time of any new data or updates to updated data included in the current ODM file. This attribute is implied, and if omitted, it is assumed that the AsOfDateTime is equal to the CreationDateTime. It is an error to supply an AsOfDateTime that is later than the CreationDateTime.
The ODMVersion attribute was not defined in ODM 1.1, so a missing ODMVersion should be interpreted as "1.1".
Documents based on ODM 2.0 must have ODMVersion="2.0" set in order to use the new features in this version. Documents based on ODM 1.3.2 must have ODMVersion="1.3.2" set in order to use the new features in this version. Documents based on ODM 1.2.0 must have ODMVersion="1.2", documents based ODM 1.3.0 must have ODMVersion="1.3" and documents based on ODM 1.3.1 must have ODMVersion="1.3.1" for backwards compatibility purposes.
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