<?xml version="1.0"?>

<!DOCTYPE exa SYSTEM "exa-1.ext" [

<!ELEMENT exa (a|b)*>

<!ENTITY ext SYSTEM "ext.elem">
<!ENTITY % ext SYSTEM "ext.decl">

%ext;

<!ELEMENT a (b*)>
<!ATTLIST a num NMTOKEN #FIXED "0">
]>

<exa>
<a num="a" id="id1">
<a id="id1"/>
&ext;
<b nmu="1"> </b>
</a>
</exa>

