MLA

O'Neill, Eugene, 1888-1953. Crouching on beach, siting on dunes. Box 109, folder 1899. [1934]. https://collections.library.yale.edu/catalog/2026493.

APA, 6th edition

O'Neill, Eugene, 1888-1953. (["Box 109, folder 1899"])([1934])[Crouching on beach, siting on dunes]. https://collections.library.yale.edu/catalog/2026493.