"Black America:" broadside
MLA
Salsbury, Nathan, 1846-1902. "Black America:" broadside. Box 1, folder 21. n.d.. https://collections.library.yale.edu/catalog/2041803.
APA, 6th edition
Salsbury, Nathan, 1846-1902. (["Box 1, folder 21"])(n.d.)["Black America:" broadside]. https://collections.library.yale.edu/catalog/2041803.