MLA

Kilpatrick, Jack Frederick (1915-1967). Letters and notes including practice in English and Latin writing, 8 pages, accompanied by an envelope. Box 1, folder 36. 1934. https://collections.library.yale.edu/catalog/15491761.

APA, 6th edition

Kilpatrick, Jack Frederick (1915-1967). (["Box 1, folder 36"])(1934)[Letters and notes including practice in English and Latin writing, 8 pages, accompanied by an envelope]. https://collections.library.yale.edu/catalog/15491761.