<att>

<att> (attribute) contains the name of an attribute appearing within running text. 22 Documentation Elements
Module tagdocs — 22 Documentation Elements
In addition to global attributes In addition to global attributes
scheme supplies an identifier for the scheme in which this name is defined.
Status Optional
Datatype 

<rng:ref name="data.enumerated"/>
data.enumerated
Sample values include:
TEI
(text encoding initiative) this attribute is part of the TEI scheme. [Default]
DBK
(docbook) this attribute is part of the Docbook scheme.
XX
(unknown) this attribute is part of an unknown scheme.
Used by
model.phrase.xml
May contain Character data only
Declaration 

<rng:element name="att">
 <rng:ref name="att.global.attributes"/>
 <rng:optional>
  <rng:attribute name="scheme" a:defaultValue="TEI">
   <rng:ref name="data.enumerated"/>
  </rng:attribute>
 </rng:optional>
 <rng:text/>
</rng:element>
element att
{
   att.global.attributes,
   attribute scheme { data.enumerated }?,
   text
}
Example
<p>The TEI defines six <soCalled>global</soCalled> attributes; their names are
<att>xml:id</att>, <att>rend</att>, <att>xml:lang</att>, <att>n</att>, <att>xml:space</att>,
and <att>xml:base</att>; <att scheme="XX">style</att> is not among them.</p>
Note
A namespace prefix may be used in order to specify the scheme as an alternative to specifying it via the scheme attribute: it takes precedence