MLA

Wilson, Edmund, 1895-1972. Rado, Sandor. Box 58, folder 1549. 1955, n.d.. https://collections.library.yale.edu/catalog/17083237.

APA, 6th edition

Wilson, Edmund, 1895-1972. (["Box 58, folder 1549"])(1955, n.d.)[Rado, Sandor]. https://collections.library.yale.edu/catalog/17083237.