<!ENTITY % ToolkitName "NMTOKEN"> <!ELEMENT autos (auto)> <!ATTLIST autos year CDATA #REQUIRED> <!ELEMENT auto (doors, engine, performance, price)> <!ATTLIST auto name CDATA #REQUIRED> <!ELEMENT doors EMPTY> <!ELEMENT engine EMPTY> <!ATTLIST engine displacement CDATA #REQUIRED horsepower CDATA #REQUIRED> <!ELEMENT performance (zeroto60, quartermile)> <!ELEMENT zeroto60 EMPTY> <!ELEMENT quartermile EMPTY> <!ATTLIST quartermile second CDATA #REQUIRED mpg CDATA #REQUIRED> <!ELEMENT price EMPTY>