xml:specialAttrs

Attribute Group Information

Attributes

QName Type Fixed Default Use Inheritable Annotation
xml:lang xs:language optional 
In due course, we should install the relevant ISO 2- and 3-letter
codes as the enumerated possible values . . .
xml:space restriction of xs:NCName optional

Source 

<xs:attributeGroup name="specialAttrs">
  <xs:attribute ref="xml:lang"/>
  <xs:attribute ref="xml:space"/>
</xs:attributeGroup>