Cite

[Untitled photograph of rock formations]

MLA

Jackson, William Henry, 1843-1942. [Untitled photograph of rock formations]. Folder 5A. [ca. 1870]. https://collections.library.yale.edu/catalog/2011315.

APA, 6th edition

Jackson, William Henry, 1843-1942. (["Folder 5A"])([ca. 1870])[[Untitled photograph of rock formations]]. https://collections.library.yale.edu/catalog/2011315.