dx:introduction 

information present outside the element or as the basic description for an attribute

Element Information

Model

dx:p
Children: dx:p

Used By

Elements dx:description, dx:element, dx:usage
Complex Types dx:descriptionType, dx:elementType, dx:valueType

Source 

<xs:element name="introduction">
  <xs:annotation>
    <xs:documentation>information present outside the element or as the basic description for an attribute</xs:documentation>
  </xs:annotation>
  <xs:complexType>
    <xs:sequence maxOccurs="unbounded">
      <xs:element ref="dx:p"/>
    </xs:sequence>
  </xs:complexType>
</xs:element>

Sample