9. [Waterfall.]
MLA
McClintock, Walter, 1870-1949. 9. [Waterfall.]. Box 60, folder 2929. 1941. https://collections.library.yale.edu/catalog/2008345.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 60, folder 2929"])(1941)[9. [Waterfall.]]. https://collections.library.yale.edu/catalog/2008345.