G785. Park. Head of Canyon. Timber and Peaks. Dark Sky.
MLA
McClintock, Walter, 1870-1949. G785. Park. Head of Canyon. Timber and Peaks. Dark Sky.. Box 108, folder 5050. 1906 Fall. https://collections.library.yale.edu/catalog/10450811.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 108, folder 5050"])(1906 Fall)[G785. Park. Head of Canyon. Timber and Peaks. Dark Sky.]. https://collections.library.yale.edu/catalog/10450811.