SF-266. First Spring Flowers and Plants. Marshy Places. Trail to Piegan Pass.
MLA
McClintock, Walter, 1870-1949. SF-266. First Spring Flowers and Plants. Marshy Places. Trail to Piegan Pass.. Box 146, folder 7706. undated. https://collections.library.yale.edu/catalog/10453851.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 146, folder 7706"])(undated)[SF-266. First Spring Flowers and Plants. Marshy Places. Trail to Piegan Pass.]. https://collections.library.yale.edu/catalog/10453851.