MLA
Hugh C. Leighton Co. (Portland, Me.). When ignorance is bliss, T'is folly to be wise : an African American man fishing, with a no fishing allowed sign. February 23, 1911. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/931qfttf1s-cor.
APA, 6th edition
Hugh C. Leighton Co. (Portland, Me.). (February 23, 1911)[When ignorance is bliss, T'is folly to be wise : an African American man fishing, with a no fishing allowed sign]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/931qfttf1s-cor.
Chicago
Hugh C. Leighton Co. (Portland, Me.), When ignorance is bliss, T'is folly to be wise : an African American man fishing, with a no fishing allowed sign, February 23, 1911, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/931qfttf1s-cor.