Cite

At the head of Paradise Valley, looking back toward The Sphinx. 63

MLA

At the Head of Paradise Valley, Looking Back toward The Sphinx. 63. 0AD. https://collections.library.yale.edu/catalog/2015446.

APA, 6th edition

At the head of Paradise Valley, looking back toward The Sphinx. 63. (0 C.E.). [Photographic prints, Photographs, Stereographs]. https://collections.library.yale.edu/catalog/2015446.