Lexicon Graph document grammar

This is the Lexicon Graph document grammar refered to in the book.

<!--  
        LG DTD 2003-12-01
        Version 0.1
        Thorsten Trippel

        Universitaet Bielefeld
        Fakultaet fuer Linguistik und Literaturwissenschaft
        DTD for the Lexicon Graph Model implementation
-->

<!-- ENTITIES -->

<!-- ELEMENTS -->

<!--  LG is the root element for Lexicon Graph implementation 
 -->

<!ELEMENT LG            (lexitems,relations,knowledge)>

<!--  Three basic elements per lexicon -->

<!ELEMENT lexitems     (lexitem+)>
<!ELEMENT relations     (relation+)>
<!ELEMENT knowledge     (know+)>

<!-- lexitems -->

<!ELEMENT lexitem (#PCDATA|object)*>
<!ELEMENT relation (source+,target)>
<!ELEMENT know (conceptname*, knowcat+)>
<!ELEMENT object EMPTY>
<!ELEMENT source EMPTY>
<!ELEMENT target EMPTY>
<!ELEMENT conceptname (#PCDATA)*>
<!ELEMENT knowcat (#PCDATA|like)*>
<!ELEMENT like EMPTY>

<!-- ATTRIBUTES -->

<!ATTLIST lexitem id ID #REQUIRED>
<!ATTLIST relation type CDATA #REQUIRED>
<!ATTLIST source idref IDREF #REQUIRED>
<!ATTLIST target idref IDREF #REQUIRED>
<!ATTLIST know id ID #REQUIRED>
<!ATTLIST like idref IDREF #REQUIRED>
<!ATTLIST object 
                 type CDATA #IMPLIED
                 uri CDATA #REQUIRED>