MLA

Williams, William Carlos, 1883-1963. Lyle, David. Box 13, folder 406-410. 1947-1951. https://collections.library.yale.edu/catalog/17049502.

APA, 6th edition

Williams, William Carlos, 1883-1963. (["Box 13, folder 406-410"])(1947-1951)[Lyle, David]. https://collections.library.yale.edu/catalog/17049502.