--- /dev/null
+<!DOCTYPE a [
+
+<!ELEMENT a (b | (c, d)* | (e, f)+ | g?)>
+<!ELEMENT b (#PCDATA | a)*>
+<!ELEMENT c EMPTY>
+<!ELEMENT d ANY>
+<!ELEMENT e EMPTY>
+<!ELEMENT f EMPTY>
+<!ELEMENT g EMPTY>
+
+<!ATTLIST a u CDATA #IMPLIED
+ v NMTOKEN "huhu"
+ w (q|p) #REQUIRED
+ x NOTATION (n1|n2) "n1"
+ y ENTITY #IMPLIED>
+
+<!NOTATION n1 SYSTEM "/bin/n1-processor">
+<!NOTATION n2 SYSTEM "/bin/n2-processor">
+
+<!ENTITY u1 SYSTEM "file-u1" NDATA n1>
+<!ENTITY u2 SYSTEM "file-u2" NDATA n2>
+
+<?pi1 args ...?>
+]>
+
+<a u="1" w="q" x="n2">
+ <b>
+ <?pi2 args ...?>
+ This is text!
+ <a w="p" y="u1">
+ <c/>
+ <d/>
+ </a>
+ </b>
+</a>
+
+<?pi3 args ...?>