MLA

Gounod Society (New Haven, Conn.). Lists of members. Box 1, folder 6. 1887-1919. https://collections.library.yale.edu/catalog/32551323.

APA, 6th edition

Gounod Society (New Haven, Conn.). (["Box 1, folder 6"])(1887-1919)[Lists of members]. https://collections.library.yale.edu/catalog/32551323.