Metadata elements include information that is located within
the <topicmeta> element (in maps) or <prolog> element (in topics),
as well as indexing elements that can be placed in additional locations
within topic content.
The delayed conref resolution domain provides several elements
for use when using DITA in situations that enable delayed or run time
resolution of conref. The elements allow users to resolve some conref
values statically, while delaying others for later resolution.