I have a product that supports multilingual variants of field content. I would like to map the content of records to Bibliontology RDF for export and import.
Field elements in the application are of two types. In the terms I use locally, these are the "headline entry" (containing the original form) and "supplemental entries" (each containing a variant with an RFC 5646 tag indicating its language and script).
A language tag is optional on the "headline entry": it may or may not be set. However, because the headline entry represents the original value, (without translation or transliteration) it is important that it be correctly identfied when data is exported in RDF and re-imported. I'm not sure how to accomplish that.
RDF allows use of the xml:lang attribute to specify the language of a node or property element: http://www.w3.org/TR/REC-rdf-syntax/#section-Syntax-languages
Here is a sample of our current output:
In this example, dcterms:title has two forms. The first has no value for xml:lang, and can safely be treated as the headline entry. However, if the first entry is given an attribute xml:lang="ja", then because (as I understand RDF) there is no sequential relation between the two alternatives, selecting the "first" as the headline entry is not possible. (The dcterms:lang value cannot be used as a hint, since it applies to the language of the underlying source identified by the record, not of the field itself, and the two may differ.)
If I am mistaken and the dcterms:title elements here can be treated as a sequence, that would offer the simplest solution. If not, perhaps I am overlooking something basic in RDF generally or Bibo specifically?
Any advice greatly appreciated.