- <!ELEMENT geology (volcano)+>
- <!ELEMENT volcano (location,height,type,eruption+,magma,comment?)>
- <!ATTLIST volcano name CDATA #IMPLIED>
- <!ELEMENT location (#PCDATA)>
- <!ELEMENT height EMPTY>
- <!ATTLIST height value CDATA #IMPLIED
- unit CDATA #IMPLIED>
- <!ELEMENT type (#PCDATA)>
- <!ELEMENT eruption (#PCDATA)>
- <!ELEMENT magma (#PCDATA)>
- <!ELEMENT comment (#PCDATA)>