MLA

Bryher, 1894-1983. Pearson, Norman Holmes. Box 42, folder 1515-1556. 1953-60. https://collections.library.yale.edu/catalog/10081409.

APA, 6th edition

Bryher, 1894-1983. (["Box 42, folder 1515-1556"])(1953-60)[Pearson, Norman Holmes]. https://collections.library.yale.edu/catalog/10081409.