MLA

Wescott, Glenway, 1901-1987. Montgomery, George H.. Box 80, folder 1188. 1948-51, n.d.. https://collections.library.yale.edu/catalog/17065016.

APA, 6th edition

Wescott, Glenway, 1901-1987. (["Box 80, folder 1188"])(1948-51, n.d.)[Montgomery, George H.]. https://collections.library.yale.edu/catalog/17065016.