From the introduction: "This paper seeks to justify a bistratal analysis for certain clauses in Southeastern Tepehuan (SET). In intransitive clauses (where the subject is the only nominal), or in transitive clauses where a direct object is also present, the account of subject and object agreement is straight forward. But in transitive clauses where a notional indirect object or benefactee is present as well, these are advanced to the status of direct object; they replace the initial direct object and determine object agreement on the verb. In section 1 I give the pertinent facts about term marking and show that verbs agree with their final direct objects. In section 2 I give evidence for the 3-2, benefactee-2, and comitative-2 advancements. Then in section 3 I argue that this analysis is preferable to either of two monostratal analyses that could be proposed to describe these facts."
Willett, Thomas L.
"Advancements to direct object in Southeastern Tepehuan,"
Work Papers of the Summer Institute of Linguistics, University of North Dakota Session: Vol. 25, Article 4.
Available at: https://commons.und.edu/sil-work-papers/vol25/iss1/4