MLA

Gabo, Naum, 1890-1977. Dorner, Alexander. Box 7. 1939-1980. https://collections.library.yale.edu/catalog/17433981.

APA, 6th edition

Gabo, Naum, 1890-1977. (["Box 7"])(1939-1980)[Dorner, Alexander]. https://collections.library.yale.edu/catalog/17433981.