<?xml version="1.0" standalone="yes"?>
<!DOCTYPE SCHEDULE [

   <!NOTATION ISODATE SYSTEM 
     "http://www.iso.ch/cate/d15903.html">   
   <!NOTATION USDATE SYSTEM 
"http://es.rice.edu/ES/humsoc/Galileo/Things/gregorian_calendar.html">   
   
   <!ELEMENT SCHEDULE (APPOINTMENT*)>
   <!ELEMENT APPOINTMENT (NOTE, DATE, TIME?)>
    
   <!ELEMENT NOTE (#PCDATA)>
   <!ELEMENT DATE (#PCDATA)>
   <!ELEMENT TIME (#PCDATA)>

   <!ATTLIST DATE FORMAT NOTATION (ISODATE | USDATE) #IMPLIED>
  
]>
<SCHEDULE>
  <APPOINTMENT>
    <NOTE>Deliver presents</NOTE>
    <DATE FORMAT="USDATE">12-25-1999</DATE>
  </APPOINTMENT>
  <APPOINTMENT>
    <NOTE>Party like it's 1999</NOTE>
    <DATE FORMAT="ISODATE">19991231</DATE>
  </APPOINTMENT>
</SCHEDULE>
