Type IV: Classificatory noun incorporation [...] A number of languages exhibit NI not only of Types I-III, but of a fourth type as well. A relatively general N stem is incorporated to narrow scope of the V, as in Type III; but the compound stem can be accompained by a more specific external NP which identifies the argument implied by the IN. Once the argument has been identified, the general, incorporable N stem is sufficient to qualify V's involving this argument insubsequent discourse. Since only general N's are incorporated for this purpose, a classificatory system often results. Nominal are classified according to the particular general N stem that is incorporated to qualify V's directed at them.
- Mithun (2004), Pag. 132