+<!ELEMENT mlt (profile | producer | playlist | tractor | multitrack)+ >
+<!ELEMENT profile EMPTY >
+<!ATTLIST profile
+ name CDATA #IMPLIED
+ description CDATA #IMPLIED
+ display_aspect_den CDATA #IMPLIED
+ display_aspect_num CDATA #IMPLIED
+ frame_rate_den CDATA #REQUIRED
+ frame_rate_num CDATA #REQUIRED
+ height CDATA #REQUIRED
+ progressive CDATA #REQUIRED
+ sample_aspect_den CDATA #REQUIRED
+ sample_aspect_num CDATA #REQUIRED
+ width CDATA #REQUIRED
+>