Police arresting three protesters

Chicago citation style
Hamilton, Jack. Police arresting three protesters. 1968-09. Retrieved from the Digital Public Library of America, http://content.mpl.org/cdm/ref/collection/HstoricPho/id/6470. (Accessed December 14, 2019.)
APA citation style
Hamilton, Jack, (1968-09) Police arresting three protesters. Retrieved from the Digital Public Library of America, http://content.mpl.org/cdm/ref/collection/HstoricPho/id/6470
MLA citation style
Hamilton, Jack. Retrieved from the Digital Public Library of America <http://content.mpl.org/cdm/ref/collection/HstoricPho/id/6470>.
Note: These citations are programmatically generated and may be incomplete.