DTD - 来自网络的实例

 <!DOCTYPE TVSCHEDULE [

 <!ELEMENT TVSCHEDULE (CHANNEL+)>
 <!ELEMENT CHANNEL (BANNER,DAY+)>
 <!ELEMENT BANNER (#PCDATA)>
 <!ELEMENT DAY (DATE,(HOLIDAY|PROGRAMSLOT+)+)>
 <!ELEMENT HOLIDAY (#PCDATA)>
 <!ELEMENT DATE (#PCDATA)>
 <!ELEMENT PROGRAMSLOT (TIME,TITLE,DESCRIPTION?)>
 <!ELEMENT TIME (#PCDATA)>
 <!ELEMENT TITLE (#PCDATA)> 
 <!ELEMENT DESCRIPTION (#PCDATA)>

 <!ATTLIST TVSCHEDULE NAME CDATA #REQUIRED>
 <!ATTLIST CHANNEL CHAN CDATA #REQUIRED>
 <!ATTLIST PROGRAMSLOT VTR CDATA #IMPLIED>
 <!ATTLIST TITLE RATING CDATA #IMPLIED>
 <!ATTLIST TITLE LANGUAGE CDATA #IMPLIED>
 ]> 

 <!DOCTYPE NEWSPAPER [

 <!ELEMENT NEWSPAPER (ARTICLE+)>
 <!ELEMENT ARTICLE (HEADLINE,BYLINE,LEAD,BODY,NOTES)>
 <!ELEMENT HEADLINE (#PCDATA)>
 <!ELEMENT BYLINE (#PCDATA)>
 <!ELEMENT LEAD (#PCDATA)>
 <!ELEMENT BODY (#PCDATA)>
 <!ELEMENT NOTES (#PCDATA)>

 <!ATTLIST ARTICLE AUTHOR CDATA #REQUIRED>
 <!ATTLIST ARTICLE EDITOR CDATA #IMPLIED>
 <!ATTLIST ARTICLE DATE CDATA #IMPLIED>
 <!ATTLIST ARTICLE EDITION CDATA #IMPLIED>

 <!ENTITY NEWSPAPER "Vervet Logic Times">
 <!ENTITY PUBLISHER "Vervet Logic Press">
 <!ENTITY COPYRIGHT "Copyright 1998 Vervet Logic Press">

 ]> 

 <!DOCTYPE CATALOG [

 <!ENTITY AUTHOR "John Doe">
 <!ENTITY COMPANY "JD Power Tools, Inc.">
 <!ENTITY EMAIL "jd@jd-tools.com">

 <!ELEMENT CATALOG (PRODUCT+)>

 <!ELEMENT PRODUCT
 (SPECIFICATIONS+,OPTIONS?,PRICE+,NOTES?)>
 <!ATTLIST PRODUCT
 NAME CDATA #IMPLIED
 CATEGORY (HandTool|Table|Shop-Professional) "HandTool"
 PARTNUM CDATA #IMPLIED
 PLANT (Pittsburgh|Milwaukee|Chicago) "Chicago"
 INVENTORY (InStock|Backordered|Discontinued) "InStock">

 <!ELEMENT SPECIFICATIONS (#PCDATA)>
 <!ATTLIST SPECIFICATIONS
 WEIGHT CDATA #IMPLIED
 POWER CDATA #IMPLIED>

 <!ELEMENT OPTIONS (#PCDATA)>
 <!ATTLIST OPTIONS
 FINISH (Metal|Polished|Matte) "Matte"
 ADAPTER (Included|Optional|NotApplicable) "Included"
 CASE (HardShell|Soft|NotApplicable) "HardShell">

 <!ELEMENT PRICE (#PCDATA)>
 <!ATTLIST PRICE
 MSRP CDATA #IMPLIED
 WHOLESALE CDATA #IMPLIED
 STREET CDATA #IMPLIED
 SHIPPING CDATA #IMPLIED>

 <!ELEMENT NOTES (#PCDATA)>

 ]>