Powell , A. M. ., Powell, S. A. . and Jackson, C. . (2017) “Documented chromosome numbers 2017:1. Miscellaneous counts mostly from western Texas (U.S.A.), one each from New Mexico (U.S.A.) and Mexico”, Journal of the Botanical Research Institute of Texas, 11(1), pp. 143–146. doi: 10.17348/jbrit.v11.i1.1145.