BRIT Press. 2018. “Intermountain Flora: Vascular Plants of the Intermountain West, U.S.A. Volume 7, Potpourri: Keys, History, Authors, Artists, Collectors, Beardtongues, Glossary, Indices”. Journal of the Botanical Research Institute of Texas 12 (2):548. https://doi.org/10.17348/jbrit.v12.i2.958.