<!ENTITY foo 'bar'>
<!ELEMENT x (banana)*>
<!ELEMENT banana (#PCDATA)>

<!ATTLIST x xmlns:xi CDATA #FIXED "http://www.w3.org/2001/XInclude">
<!ELEMENT xi:include (xi:fallback?)>
<!ATTLIST xi:include
    xmlns:xi CDATA      #FIXED    "http://www.w3.org/2001/XInclude"
    href     CDATA      #IMPLIED
    parse    (xml|text) "xml"
>

<!ATTLIST banana
    id     ID    #IMPLIED
    idref  IDREF #IMPLIED
>