<grammar xmlns="http://relaxng.org/ns/structure/1.0">
<define name="cd.token.unary.class" combine="choice">
<choice>
<ref name="int.token"/>
<ref name="diff.token"/>
<ref name="grad.token"/>
<ref name="curl.token"/>
<ref name="laplacian.token"/>
</choice>
</define>
<define name="cd.token.binary.class" combine="choice">
<choice>
<ref name="defint.token"/>
<ref name="defintset.token"/>
</choice>
</define>
<define name="cd.token.nary.class" combine="choice">
<ref name="partialdiff.token"/>
</define>
<define name="cd.binder.class" combine="choice">
<choice>
<ref name="intalg.token"/>
<ref name="Diff.token"/>
</choice>
</define>
<define name="int.content">
<ref name="Token.type"/>
</define>
<define name="int.token">
<element name="int">
<ref name="int.content"/>
</element>
</define>
<define name="defint.content">
<ref name="Token.type"/>
</define>
<define name="defint.token">
<element name="defint">
<ref name="defint.content"/>
</element>
</define>
<define name="defintset.content">
<ref name="Token.type"/>
</define>
<define name="defintset.token">
<element name="defintset">
<ref name="defintset.content"/>
</element>
</define>
<define name="intalg.content">
<ref name="Token.type"/>
</define>
<define name="intalg.token">
<element name="intalg">
<ref name="intalg.content"/>
</element>
</define>
<define name="diff.content">
<ref name="Token.type"/>
</define>
<define name="diff.token">
<element name="diff">
<ref name="diff.content"/>
</element>
</define>
<define name="Diff.content">
<ref name="Token.type"/>
</define>
<define name="Diff.token">
<element name="Diff">
<ref name="Diff.content"/>
</element>
</define>
<define name="partialdiff.content">
<ref name="Token.type"/>
<optional>
<attribute name="type">
<ref name="MathMLtype"/>
</attribute>
</optional>
</define>
<define name="partialdiff.token">
<element name="partialdiff">
<ref name="partialdiff.content"/>
</element>
</define>
<define name="divergence.content">
<ref name="Token.type"/>
</define>
<define name="divergence.token">
<element name="divergence">
<ref name="divergence.content"/>
</element>
</define>
<define name="grad.content">
<ref name="Token.type"/>
</define>
<define name="grad.token">
<element name="grad">
<ref name="grad.content"/>
</element>
</define>
<define name="curl.content">
<ref name="Token.type"/>
</define>
<define name="curl.token">
<element name="curl">
<ref name="curl.content"/>
</element>
</define>
<define name="laplacian.content">
<ref name="Token.type"/>
</define>
<define name="laplacian.token">
<element name="laplacian">
<ref name="laplacian.content"/>
</element>
</define>
</grammar>