When using a hierarchical subject scheme, this
element indicates the level of this list of keywords. Level 1 is the highest
level.
Obligation
Optional
Repeatable
No
NAA Metadata
No
Default Value
–
Attributes
Attribute Name/Type
Definition
vers:schemeCDATA
(Optional) A reference to the scheme that controls
the values of this element. Would normally only be present if there is a
published scheme that can be referred to by a viewer.
