Cite

Unknown photographer Three men seated before open tent; two men seated at desks just inside tent; three young boys seated on ground in foreground. Later 19th century photograph, 6-3/8 X 9

MLA

Simpson, Randolph Linsly, 1927-1992. Unknown photographer Three men seated before open tent; two men seated at desks just inside tent; three young boys seated on ground in foreground. Later 19th century photograph, 6-3/8 X 9. Box 16, folder 754. 1862. https://collections.library.yale.edu/catalog/2005290.

APA, 6th edition

Simpson, Randolph Linsly, 1927-1992. (["Box 16, folder 754"])(1862)[Unknown photographer Three men seated before open tent; two men seated at desks just inside tent; three young boys seated on ground in foreground. Later 19th century photograph, 6-3/8 X 9]. https://collections.library.yale.edu/catalog/2005290.