MLA

Gilder, Jeannette L. (Jeannette Leonard), 1849-1916. Rossetti, Christina Georgina. Box 1. 1885 Apr 20. https://collections.library.yale.edu/catalog/2005477.

APA, 6th edition

Gilder, Jeannette L. (Jeannette Leonard), 1849-1916. (["Box 1"])(1885 Apr 20)[Rossetti, Christina Georgina]. https://collections.library.yale.edu/catalog/2005477.