The subclause levels of this section suggest that Included Schema and Included Annotations are independent declarations from the $Reference declaration. However, they should be documented as parts of the $Reference declaration.
Related to this, 4.1 Reference asserts that it is used to bring in part of the referenced document. However, both $Include and $IncludedAnnotations is documented as optional. Either $Reference can bring in all of a referenced document, or at least one of $Include or $IncludedAnnotations must be specified.
Note that edmx.xsd does not resolve this issue since it also allows the possibility that neither Include or IncludeAnnotations is specified.
A trivial issue is that both 'include' and 'included' are used to refer to the same functionality in this section.