テキストラテック語族
Campbell, Lyle and David Oltrogge, 1980, Proto-Tol (Jicaque), International Journal of American Linguistics, 46:205-223
Campbell, Lyle. (1979). Middle American languages. In L. Campbell & M. Mithun (Eds.), The languages of native America: Historical and comparative assessment (pp. 902-1000). Austin: University of Texas Press.