I have a doubt with the declaration of External Unparsed General
Entities. I though the declaration was like this:
'<!ENTITY' S name S ['PUBLIC' public-id] S 'SYSTEM' S uri S notation S '>'
for example :
<!NOTATION JPG SYSTEM "format of my photo">
<!ENTITY photo SYSTEM "http://www.myweb.com/photo.jpg" JPG>
But, i have found this decalration in the especifications:
4.2.2 External Entities
[Definition: If the entity is not internal, it is an external
entity, declared as follows:]
External Entity Declaration
 ExternalID ::= 'SYSTEM' S SystemLiteral | 'PUBLIC' S
PubidLiteral S SystemLiteral
 NDataDecl ::= S 'NDATA' S Name [VC: Notation Declared]
If the NDataDecl is present, this is a general unparsed entity;
otherwise it is a parsed entity.
What is NData and where is called ? do i have to write 'NDATA' before
Thank you very much!