F. W.  Gould, Ali, A., and Fairbrothers, D. E., ?A revision of Echinochloa in the United States?, American Midland Naturalist, vol. 87, pp. 36-59, 1972.

D. E.  Fairbrothers, ?Relationships in the Capillaria Group of Panicum in Arizona and New Mexico?, American Journal of Botany, vol. 40, pp. 708-714, 1953.