<ptr>

<ptr> (pointer) defines a pointer to another location. 3.6 Simple Links and Cross-References 16.1 Links
Modulecore — 3 Elements Available in All TEI Documents
Attributes att.pointing (@type, @evaluate) att.declaring (@decls)
targetspecifies the destination of the pointer by supplying one or more URI References
Status Required
Datatype 1–∞ occurrences of 

<rng:ref name="data.pointer"/>
data.pointer
separated by whitespace
Values One or more syntactically valid URI references, separated by whitespace. Because whitespace is used to separate URIs, no whitespace is permitted inside a single URI. If a whitespace character is required in a URI, it should be escaped with the normal mechanism, e.g. TEI%20Consortium.
cRef(canonical reference) specifies the destination of the pointer by supplying a canonical reference from a scheme defined in a refsDecl element in the TEI header
Status Required
Datatype 1–∞ occurrences of 

<rng:ref name="data.word"/>
data.word
separated by whitespace
Values the result of applying the algorithm for the resolution of canonical references (described in section 16.2.5 Canonical References) should be a valid URI reference to the intended target
Note
The refsDecl to use may be indicated with the decls attribute.
Currently these Guidelines only provide for a single canonical reference to be encoded on any given ptr element.
Used byaltGrp joinGrp linkGrp listRef model.ptrLike
May containEmpty element
Declaration

<rng:element name="ptr">
<rng:ref name="att.global.attributes"/>
<rng:ref name="att.pointing.attributes"/>
<rng:ref name="att.declaring.attributes"/>
<rng:choice>
 <rng:attribute name="target">
  <rng:list>
   <rng:oneOrMore>
    <rng:ref name="data.pointer"/>
   </rng:oneOrMore>
  </rng:list>
 </rng:attribute>
 <rng:attribute name="cRef">
  <rng:list>
   <rng:oneOrMore>
    <rng:ref name="data.word"/>
   </rng:oneOrMore>
  </rng:list>
 </rng:attribute>
</rng:choice>
<rng:empty/>
</rng:element>
element ptr
{
   att.global.attributes,
   att.pointing.attributes,
   att.declaring.attributes,
   (
      attribute target { list { data.pointer+ } }
    | attribute cRef { list { data.word+ } }
   ),
   empty
}
Example
<ptr target="#p143 #p144"/>
<ptr target="http://www.tei-c.org"/>
Note
The target and cRef attributes are mutually exclusive.