Cite

Down the zig-zags from Whitney Pass, called the Staircase or The Ladder. 166

MLA

Down the Zig-Zags from Whitney Pass, Called the Staircase or The Ladder. 166. 0AD. https://collections.library.yale.edu/catalog/2016913.

APA, 6th edition

Down the zig-zags from Whitney Pass, called the Staircase or The Ladder. 166. (0 C.E.). [Photographic prints, Photographs, Stereographs]. https://collections.library.yale.edu/catalog/2016913.