MLA

Stieglitz, Alfred, 1864-1946. Newhall, Beaumont. Box 37, folder 869. 1939-45. https://collections.library.yale.edu/catalog/17105645.

APA, 6th edition

Stieglitz, Alfred, 1864-1946. (["Box 37, folder 869"])(1939-45)[Newhall, Beaumont]. https://collections.library.yale.edu/catalog/17105645.