Cite

Down the zig-zags from Whitney Pass, called the Staircase or The Ladder. 168

MLA

Down the Zig-Zags from Whitney Pass, Called the Staircase or The Ladder. 168. 0AD. https://collections.library.yale.edu/catalog/2016915.

APA, 6th edition

Down the zig-zags from Whitney Pass, called the Staircase or The Ladder. 168. (0 C.E.). [Photographic prints, Photographs, Stereographs]. https://collections.library.yale.edu/catalog/2016915.