Nonspecificity is a kind of definiteness, expressed by an interpretation of or grammatical marking on a noun or noun phrase, indicating that the speaker presumably does not know the identity of the referent(s).
The following sentence has the interpretation that the speaker does not have a particular Norwegian in mind:
Hawkins, John A. 1978.Definiteness and indefiniteness: A study in reference and grammaticality prediction. London: Croom Helm.
Anderson, Stephen R. 1985. "Inflectional morphology." In Shopen 1985d