MLA

Stieglitz, Alfred, 1864-1946. Covarrubias, Rose. Box 188, folder 3153. [1951]-57. https://collections.library.yale.edu/catalog/17105681.

APA, 6th edition

Stieglitz, Alfred, 1864-1946. (["Box 188, folder 3153"])([1951]-57)[Covarrubias, Rose]. https://collections.library.yale.edu/catalog/17105681.