The <apiPackage> element provides the name of the API package, module, public class members, namespace and all the elements that are necessary to describe its components.
The <apiPackage> contain a list of items with first sentence summaries for this API items.
The <apiPackage> element requires an ID attribute as an anchor point. This ID is the target for references by <link> or <xref> elements (conref and keyref attributes), and for other internal specialization elements that refer to this <apiPackage> content. Use a unique key such as fully qualified package name for the named API reference.
apiClassifier, apiDetail, apiName, apiOperation, apiPackage, apiValue, prolog, related-links, shortdesc
( (apiName) then (shortdesc) then (prolog) (optional) then (apiDetail) then (related-links) (optional) then (apiPackage or apiClassifier or apiOperation or apiValue) (any number))
topic/topic reference/reference apiRef/apiRef