MLA

Grenfell, Wilfred Thomason, Sir, 1865-1940. Hospital. Box 41, folder 13. 1855-1958, undated. https://collections.library.yale.edu/catalog/10009141.

APA, 6th edition

Grenfell, Wilfred Thomason, Sir, 1865-1940. (["Box 41, folder 13"])(1855-1958, undated)[Hospital]. https://collections.library.yale.edu/catalog/10009141.