MLA

Byron, Robert, 1905-1941. Drawings from travels including Athos, Persia, Afghanistan and other unidentified locations. Box 65, folder 883. undated. https://collections.library.yale.edu/catalog/2107246.

APA, 6th edition

Byron, Robert, 1905-1941. (["Box 65, folder 883"])(undated)[Drawings from travels including Athos, Persia, Afghanistan and other unidentified locations]. https://collections.library.yale.edu/catalog/2107246.