From the introduction: "This paper deals with indirect objects in Mazatec. It has two fairly modest goals. The first is to describe the superficial characteristics of indirect objects in Mazatec. We claim that they occur as prepositional phrases which are obligatorily incorporated into the verb (in a specific way described below). The second goal is to describe the constructions in which indirect objects occur in Mazatec. We do this primarily within the framework of Relational Grammar (Perlmutter 1983a, Perlmutter and Rosen 1984), claiming that indirect objects occur in simple clauses and also in clauses with Benefactive-3 Advancement, 2-3 Retreat (personal and impersonal), and (impersonal) Inversion. 3-chomeurs, which sometimes occur, are marked differently from final indirect objects. All of these claims are novel for Mazatec. In addition, this is the first time for which such constructions have been posited for any Otomanguean language."
Agee, Daniel M. and Marlett, Stephen A.
"Indirect objects and incorporation in Mazatec,"
Work Papers of the Summer Institute of Linguistics, University of North Dakota Session: Vol. 30, Article 1.
Available at: https://commons.und.edu/sil-work-papers/vol30/iss1/1