This falls under the general problem of the use of strings instead of IRIs; different forms of code that are associated with the same "language" could be associated with an IRI referring to that "language" .

Alternatively,  two Identifiers could be declared and asserted to be sameAs ,  but that approach is more complicated.

"Language" left unpacked to avoid issues of extended language tags

On Jun 29, 2014 4:26 PM, "Stuart Yeates" <[log in to unmask]> wrote:
On 06/28/2014 01:25 AM, Jody L. DeRidder wrote:
I just saw this posted on Twitter.

Rob Sanderson is concerned about the ways in which Bibframe does NOT
worked in the linked data environment, and is trying to effectively
communicate the issues.  He's asking for feedback:

My biggest issue (that's not covered in the doc, but which I've already fed to the doc's authors) is that BIBFRAME mandates three-letter language codes, where available, while core RDA mandates two-letter language codes, where available.

This requires every app that wants to interoparate BIBFRAME with any thing else (and indeed any app that wants to compare BIBFRAME language codes with the language codes on RDF plain-text labels) to have extensive lookup tables.