SF-141. Trail.
MLA
McClintock, Walter, 1870-1949. SF-141. Trail.. Box 145, folder 7581. undated. https://collections.library.yale.edu/catalog/10453726.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 145, folder 7581"])(undated)[SF-141. Trail.]. https://collections.library.yale.edu/catalog/10453726.