mei:identifier 

An alpha-numeric string that establishes the identity of the described
material.

Element Information

Model

(mei:pb) | (mei:address) | (mei:annot) | (mei:bibl) | (mei:date) | mei:abbr | mei:expan | (mei:identifier) | (mei:lb) | (mei:num) | mei:name | mei:corpName | mei:persName | (mei:repository) | (mei:geogName) | mei:rend | mei:stack | (mei:title) | (mei:fig) | mei:bloc | mei:country | mei:district | mei:geogFeat | mei:region | mei:settlement | mei:postBox | mei:postCode | mei:street | mei:periodName | mei:styleName | mei:ptr | mei:ref | mei:symbol | mei:mei_model.editLike | mei:mei_model.transcriptionLike
Children: mei:abbr, mei:address, mei:annot, mei:bibl, mei:bloc, mei:corpName, mei:country, mei:date, mei:district, mei:expan, mei:fig, mei:geogFeat, mei:geogName, mei:identifier, mei:lb, mei:mei_model.editLike, mei:mei_model.transcriptionLike, mei:name, mei:num, mei:pb, mei:periodName, mei:persName, mei:postBox, mei:postCode, mei:ptr, mei:ref, mei:region, mei:rend, mei:repository, mei:settlement, mei:stack, mei:street, mei:styleName, mei:symbol, mei:title

Attributes

QName Type Fixed Default Use Inheritable Annotation
analog xs:string optional 
Contains a reference to a field or element in another descriptive encoding
system to which this MEI element is comparable.
authURI mei:mei_data.URI optional 
The web-accessible location of the controlled vocabulary from which the
value is taken.
authority xs:string optional 
A name or label associated with the controlled vocabulary from which the
value is taken.
facs restriction of list of mei:mei_data.URI optional 
Permits the current element to reference a facsimile surface or image zone
which corresponds to it.
label xs:string optional 
Provides a name or label for an element. The value may be any
string.
n optional 
Provides a number-like designation for an element.
subtype xs:NMTOKEN optional 
Provide any sub-classification for the element, additional to that given
by its type attribute.
type xs:NMTOKEN optional 
Characterizes the element in some sense, using any convenient
classification scheme or typology.
xml:base mei:mei_data.URI optional 
Provides a base URI reference with which applications can resolve relative
URI references into absolute URI references.
xml:id xs:ID optional 
Regularizes the naming of an element and thus facilitates building links
between it and other resources. Each id attribute within a document must have a unique
value.

Used By

Element Groups mei:mei_model.identifierLike, mei:mei_model.identifierLike_alternation, mei:mei_model.identifierLike_sequence, mei:mei_model.identifierLike_sequenceOptional, mei:mei_model.identifierLike_sequenceOptionalRepeatable, mei:mei_model.identifierLike_sequenceRepeatable

Source 

<xs:element name="identifier">
  <xs:annotation>
    <xs:documentation>An alpha-numeric string that establishes the identity of the described material.</xs:documentation>
  </xs:annotation>
  <xs:complexType mixed="true">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
      <xs:group ref="mei:mei_model.textphraseLike"/>
      <xs:element ref="mei:mei_model.editLike"/>
      <xs:element ref="mei:mei_model.transcriptionLike"/>
    </xs:choice>
    <xs:attributeGroup ref="mei:mei_att.authorized.attributes"/>
    <xs:attributeGroup ref="mei:mei_att.bibl.attributes"/>
    <xs:attributeGroup ref="mei:mei_att.common.attributes"/>
    <xs:attributeGroup ref="mei:mei_att.facsimile.attributes"/>
    <xs:attributeGroup ref="mei:mei_att.typed.attributes"/>
  </xs:complexType>
</xs:element>

Sample