There is an example under "Bad Data":

<!--  BIBFRAME Work -->
<*Play* id = 
       <title>Quatuor pour trois violons et violoncelle</title>
       <creator resource = "http://bibframe/auth/person/franklin" />
<!--  BIBFRAME Authority -->
<*Person* id="http://bibframe/auth/person/franklin">
       <label>Franklin, Benjamin, 1706-1790</label>
       <relationToWork>supposed compeser.</relationToWork>
resource="" />
       <hasVIAFLink resource="" />
       <hasDNBLink resource="" />

There is a problem with "<relationToWork>supposed 
compeser.</relationToWork>" that goes beyond the bad data.

I believe that someone else mentioned this, but if "relationToWork" is a 
property of the Person, then that Person ID cannot be used for any other 
relationship (e.g. "author") because as expressed here relationToWork is 
being said about the Person, period. There needs instead to be a triple 
that has:

WorkURI - relationToWork - PersonURI

This then states the relationship of the Person to that particular work, 
and doesn't change the underlying definition of the Person. 
Unfortunately, this isn't possible when the value of "relationToWork" is 
not a URI, because properties (the middle parts of the triples) have to 
be URIs. For example, if this information were coded using the MARC 
relator standard "<>" then you 
could say: - -

Which means that this person is the composer of the Work. (I don't know 
if there's a code for "supposed composer" but I'm pretending that "cmp" 
will do.)

To resolve this, and this is a case that we will encounter, there will 
have to be some contortions, possibly a blank node:

WorkURI - Creator -_blankA

_blankA - typeOf -
_blankA - authID -
_blankA - -  "Franklin, Benjamin, 1706-1790"
_blankA - - "supposed compeser"

The difference between the blank node and the way I interpret the 
"lightweight BIBFRAME authority" is that the blank node is a one-off -- 
it's only  usable in this one instance. There is no creation of an 
identity that could be re-used in other circumstances (although, as I've 
done above, it can link to an identity, such as an authority record). 
Blank nodes are considered last resorts by some linked data enthusiasts 
because they aren't re-usable. But there are times when you really have 
little choice.

This brings up a specific question about the BIBFRAME authority: Is it 
intended to be re-usable? Or does it have the "one-off" nature of a 
blank node?

p.s. There are undoubtedly other solutions to this problem, and I hope 
they'll get posted here.

Karen Coyle
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