MLA

Brown family, Brown, Frederick, b. 1830, Brown, Jason, 1823-1912, Brown, Wealthy. John Brown family letters : Kansas. 1855-1856. https://collections.library.yale.edu/catalog/17256906.

APA, 6th edition

Brown family, & Brown, Frederick, b. 1830, & Brown, Jason, 1823-1912, & Brown, Wealthy. (1855-1856)[John Brown family letters : Kansas]. https://collections.library.yale.edu/catalog/17256906.