Jorge Suárez linked Guaicuruan and Charruan in a Waikuru-Charrúa stock. Morris Swadesh proposed a Macro-Mapuche stock that included Matacoan, Guaicuruan, Charruan, and Mascoyan.[dubious– discuss]Terrence Kaufman (1990, 1994) said this proposal, which he called Macro-Waikurúan, deserved to be explored, but Campbell (1997) said that for the present it should not be accepted as anything more than a possibility, and by Campbell & Grondona (2012) he no longer bothers to evaluate it.
Greenberg, Joseph H. (1987). Language in the Americas. Stanford: Stanford University Press.
Kaufman, Terrence. (1990). Language history in South America: What we know and how to know more. In D. L. Payne (Ed.), Amazonian linguistics: Studies in lowland South American languages (pp. 13–67). Austin: University of Texas Press. ISBN 0-292-70414-3.
Kaufman, Terrence. (1994). The native languages of South America. In C. Mosley & R. E. Asher (Eds.), Atlas of the world's languages (pp. 46–76). London: Routledge.