"General Vaccination-Day at the Paris Academy of Medicine."
MLA
Hansen, Bert, 1944-. "General Vaccination-Day at the Paris Academy of Medicine.". Box 3, folder 16. 1870 April 23. https://collections.library.yale.edu/catalog/32326197.
APA, 6th edition
Hansen, Bert, 1944-. (["Box 3, folder 16"])(1870 April 23)["General Vaccination-Day at the Paris Academy of Medicine."]. https://collections.library.yale.edu/catalog/32326197.