Internal (Foreign Key Keyword)
Specifies whether this foreign key definition is internal (not displayed in the class documentation).
To mark this foreign key definition as internal, use the following syntax:
ForeignKey keyname(key_props) References pkg.class(ref_index) [ Internal ];
Otherwise, omit this keyword or place the word Not immediately before the keyword.
Internal class members are not displayed in the class documentation. This keyword is useful if you want users to see a class but not see all its members.
If you omit this keyword, this foreign key definition is displayed in the class documentation.