MLA

McClintock, Walter, 1870-1949. F5x7-90. Shore of Two Medicine River Near Falls. Forest. Light Rays. Traveling Tipi of Walter McClintock.. Box 148, folder 7914. undated. https://collections.library.yale.edu/catalog/10453583.

APA, 6th edition

McClintock, Walter, 1870-1949. (["Box 148, folder 7914"])(undated)[F5x7-90. Shore of Two Medicine River Near Falls. Forest. Light Rays. Traveling Tipi of Walter McClintock.]. https://collections.library.yale.edu/catalog/10453583.