MLA

Bainton, Roland H. (Roland Herbert), 1894-1984. Weigle, Luther. 56, folder 907. undated. https://collections.library.yale.edu/catalog/33599328.

APA, 6th edition

Bainton, Roland H. (Roland Herbert), 1894-1984. (["56, folder 907"])(undated)[Weigle, Luther]. https://collections.library.yale.edu/catalog/33599328.