"The District Vaccinator."
MLA
Hansen, Bert, 1944-. "The District Vaccinator.". Box 3, folder 18. 1871 May 6. https://collections.library.yale.edu/catalog/32326594.
APA, 6th edition
Hansen, Bert, 1944-. (["Box 3, folder 18"])(1871 May 6)["The District Vaccinator."]. https://collections.library.yale.edu/catalog/32326594.