MLA

Bryher, 1894-1983. Douglas, Norman. Box 9, folder 372-381. 1922-51, n.d.. https://collections.library.yale.edu/catalog/17290817.

APA, 6th edition

Bryher, 1894-1983. (["Box 9, folder 372-381"])(1922-51, n.d.)[Douglas, Norman]. https://collections.library.yale.edu/catalog/17290817.