MLA

Lucius R. Hazen (Germany). Cromwell Hall. Cromwell, Connecticut. box 1, folder 2. circa 1900-1906. https://collections.library.yale.edu/catalog/15789435.

APA, 6th edition

Lucius R. Hazen (Germany). (["box 1, folder 2"])(circa 1900-1906)[Cromwell Hall. Cromwell, Connecticut]. https://collections.library.yale.edu/catalog/15789435.