...
There are two descriptive metadata fields that let you reference associated metadata in another system: Harvard Metadata and Related Linksand Related Links (see below).
What is the purpose of the Harvard Metadata field? Use the Harvard Metadata field to reference Harvard metadata about an object that resides in another system. The most common use of this field is to add a live link to a cataloging record in Aleph or a finding aid in OASIS. Or use this field to reference a record number (but no live link) in OCLC or several other mostly legacy systems (e.g., HULPR, RLIN). These legacy Harvard metadata types were carried over from DRS1 in order facilitate the migration of DRS1 PDS document objects.
...
There are two descriptive metadata fields that let you reference associated metadata in another system: Harvard Metadata Harvard Metadata (see above) and Related Links.
What is the purpose of the Related Links field? Use the Related Links field to link to a URL that provides information related to the object. You might use this field to reference a record in VIA (since the Harvard Metadata field does not yet support VIA references) or another online system or web site at Harvard or beyond.
...