Crevels, Mily; van der Voort, Hein (2008). "4. The Guaporé-Mamoré region as a linguistic area". From Linguistic Areas to Areal Linguistics. Studies in Language Companion Series. Vol. 90. pp. 151–179. doi:10.1075/slcs.90.04cre. ISBN978-90-272-3100-0. ISSN0165-7763.
Crevels, Mily; van der Voort, Hein (2008). "4. The Guaporé-Mamoré region as a linguistic area". From Linguistic Areas to Areal Linguistics. Studies in Language Companion Series. Vol. 90. pp. 151–179. doi:10.1075/slcs.90.04cre. ISBN978-90-272-3100-0. ISSN0165-7763.