Y-1213. The Flat Top Trail.
MLA
McClintock, Walter, 1870-1949. Y-1213. The Flat Top Trail.. Box 74, folder 4342. 1905 1941. https://collections.library.yale.edu/catalog/2010803.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 74, folder 4342"])(1905 1941)[Y-1213. The Flat Top Trail.]. https://collections.library.yale.edu/catalog/2010803.