MLA

Stieglitz, Alfred, 1864-1946. Letters. Box 72, folder 1543-1546. 1934 Sep-Oct. https://collections.library.yale.edu/catalog/2041872.

APA, 6th edition

Stieglitz, Alfred, 1864-1946. (["Box 72, folder 1543-1546"])(1934 Sep-Oct)[Letters]. https://collections.library.yale.edu/catalog/2041872.