Penstemon whitedii subsp. tristis Pennell & D.D. Keck

Chicago citation style
Penstemon whitedii subsp. tristis Pennell & D.D. Keck. 21 Jun 1931. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_10163166&repo=DPLA. (Accessed November 19, 2018.)
APA citation style
(21 Jun 1931) Penstemon whitedii subsp. tristis Pennell & D.D. Keck. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_10163166&repo=DPLA
MLA citation style
Retrieved from the Digital Public Library of America <http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_10163166&repo=DPLA>.
Note: These citations are programmatically generated and may be incomplete.