Y-1804. The Country of the 'Blackfeet' Indians. [Map Shows the Four Blackfeet Reservations in the United States and Canada.]
MLA
McClintock, Walter, 1870-1949. Y-1804. The Country of the 'Blackfeet' Indians. [Map Shows the Four Blackfeet Reservations in the United States and Canada.]. Box 76, folder 4488. 1905 1941. https://collections.library.yale.edu/catalog/2010232.
APA, 6th edition
McClintock, Walter, 1870-1949. (["Box 76, folder 4488"])(1905 1941)[Y-1804. The Country of the 'Blackfeet' Indians. [Map Shows the Four Blackfeet Reservations in the United States and Canada.]]. https://collections.library.yale.edu/catalog/2010232.