MLA

Hansen, Bert, 1944-. "Another 'Federal Interference.' The struggle between Athena Hygeia and Yellow Jack.". Box 4, folder 14. 1879 April 19. https://collections.library.yale.edu/catalog/32332476.

APA, 6th edition

Hansen, Bert, 1944-. (["Box 4, folder 14"])(1879 April 19)["Another 'Federal Interference.' The struggle between Athena Hygeia and Yellow Jack."]. https://collections.library.yale.edu/catalog/32332476.