A NamedNodeMap containing the general entities, both external and internal, declared in the DTD.

  A NamedNodeMap containing the general entities, both
external and internal, declared in the DTD. Parameter entities are
not contained. Duplicates are discarded. For example in:

<!DOCTYPE 
 ex SYSTEM "ex.dtd" [ <!ENTITY foo "foo"> <!ENTITY bar 
 "bar"> <!ENTITY bar "bar2"> <!ENTITY % baz "baz"> 
 ]> <ex/>

the interface provides access to foo
and the first declaration of bar but not the second
declaration of bar or baz. Every node in
this map also implements the Entity interface.

The DOM Level 2 does not support editing entities, therefore
entities cannot be altered in any way.

  The internal subset as a string, or null if there is none.

  The internal subset as a string, or null if there is none.
This is does not contain the delimiting square brackets.

Note: The actual content returned depends on how much
information is available to the implementation. This may vary
depending on various parameters, including the XML processor used to
build the document.
Since: DOM Level 2

The name of DTD; i.e., the name immediately following the DOCTYPE keyword.

  A NamedNodeMap containing the notations declared in the DTD.

  A NamedNodeMap containing the notations declared in the
DTD. Duplicates are discarded. Every node in this map also implements
the Notation interface.

The DOM Level 2 does not support editing notations, therefore
notations cannot be altered in any way.

  The public identifier of the external subset.

  The public identifier of the external subset.
Since: DOM Level 2

  The system identifier of the external subset.

  The system identifier of the external subset. This may be an absolute
URI or not.
Since: DOM Level 2