<!ELEMENT book (title, author+, section+)> | |
<!ELEMENT title (#PCDATA)> | |
<!ELEMENT author (#PCDATA)> | |
<!ELEMENT section (title, (p | figure | section)* )> | |
<!ATTLIST section | |
id ID #IMPLIED | |
difficulty CDATA #IMPLIED> | |
<!ELEMENT p (#PCDATA)> | |
<!ELEMENT figure (title, image)> | |
<!ATTLIST figure | |
width CDATA #REQUIRED | |
height CDATA #REQUIRED > | |
<!ELEMENT image EMPTY> | |
<!ATTLIST image | |
source CDATA #REQUIRED > |