MLA

Asch, Sholem, 1880-1957. "A Briv tsu di Panes fun Poyln" (A Letter to the Gentlemen of Poland), holograph, corrected. Box 12, folder 121. n.d.. https://collections.library.yale.edu/catalog/32319562.

APA, 6th edition

Asch, Sholem, 1880-1957. (["Box 12, folder 121"])(n.d.)["A Briv tsu di Panes fun Poyln" (A Letter to the Gentlemen of Poland), holograph, corrected]. https://collections.library.yale.edu/catalog/32319562.