Bridge in Rock Creek Park entering the National Zoo, Washington, DC

Chicago citation style
Gruber, Martin A. Bridge in Rock Creek Park entering the National Zoo, Washington, DC. 1919. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Asiris_arc_291890&repo=DPLA. (Accessed November 12, 2018.)
APA citation style
Gruber, Martin A, (1919) Bridge in Rock Creek Park entering the National Zoo, Washington, DC. Retrieved from the Digital Public Library of America, http://collections.si.edu/search/results.htm?q=record_ID%3Asiris_arc_291890&repo=DPLA
MLA citation style
Gruber, Martin A. Retrieved from the Digital Public Library of America <http://collections.si.edu/search/results.htm?q=record_ID%3Asiris_arc_291890&repo=DPLA>.
Note: These citations are programmatically generated and may be incomplete.