MLA

Byron, Robert, 1905-1941. Eton College material: diary, photographs, and exhibition catalog. Box 70. 1918-1949. https://collections.library.yale.edu/catalog/2034207.

APA, 6th edition

Byron, Robert, 1905-1941. (["Box 70"])(1918-1949)[Eton College material: diary, photographs, and exhibition catalog]. https://collections.library.yale.edu/catalog/2034207.