A notation declares the format of an uparsed entity, or is used for formal declaration of a processing instruction target. A notation is a node, so the node-name contains the declared name of the entity.
public-id notation
The public-id attribute provides the public identifier of the notation, or NIL if left unspecified.
system-id notation
The system-id attribute provides the system identifier of the notation, or NIL if left unspecified.