MLA

Miłosz, Czesław, 1911-2004. A Christian looks at the ghetto, holograph. Box 92, folder 1336. undated. https://collections.library.yale.edu/catalog/10050442.

APA, 6th edition

Miłosz, Czesław, 1911-2004. (["Box 92, folder 1336"])(undated)[A Christian looks at the ghetto, holograph]. https://collections.library.yale.edu/catalog/10050442.