<!-- mpropre's DTD -->
<!-- Author: Sylvain LAGRUE -->
<!-- Email:  lagrue@cril.fr -->

<!ELEMENT pref (constraints,order)>

<!ELEMENT constraints (constr)+>

<!ELEMENT constr (#PCDATA)>
<!ATTLIST constr id ID #REQUIRED>

<!ELEMENT order (le|lt|eq|ge|gt)*>
<!ATTLIST order transitivity (on|off) "on">

<!ELEMENT le EMPTY>
<!ATTLIST le src IDREF #REQUIRED dest IDREF #REQUIRED>