<?xml version="1.0" encoding = "ISO-8859-1" ?>
<!-- DTD for student record -->
<!-- student element has all these elements in order -->
<!--     possibly multiple im elements (could be 0!) -->
<!ELEMENT student (first,middle,last,rid,address,phone,im*,courses)>

<!-- Each of the elements named here just hold unparsed data (no tags) -->
<!ELEMENT first (#PCDATA)>
<!ELEMENT middle (#PCDATA)>
<!ELEMENT last (#PCDATA)>
<!ELEMENT rid (#PCDATA)>
<!ELEMENT address (#PCDATA)>
<!ELEMENT phone (#PCDATA)>
<!ELEMENT im (#PCDATA)>

<!--  a courses element holds zero or more course elements -->
<!ELEMENT courses (course*)>
  <!--  a couses tag must have a semester attribute -->
  <!ATTLIST courses semester CDATA #REQUIRED>

<!-- a course must have a name and crn ( possibly more than one) 
     and a number -->
<!ELEMENT course (name,crn+,num)>

<!ELEMENT name (#PCDATA)>
<!ELEMENT crn (#PCDATA)>
<!ELEMENT num (#PCDATA)>