Silphium compositum A. Gray

Chicago citation style
Silphium compositum A. Gray. Sep 1891. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_12996014&repo=DPLA. (Accessed December 10, 2018.)
APA citation style
(Sep 1891) Silphium compositum A. Gray. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_12996014&repo=DPLA
MLA citation style
Retrieved from the Digital Public Library of America <http://collections.si.edu/search/results.htm?q=record_ID%3Anmnhbotany_12996014&repo=DPLA>.
Note: These citations are programmatically generated and may be incomplete.