MLA

Loy, Mina (1882-1966). "Incident". Box 6, folder 162. n.d.. https://collections.library.yale.edu/catalog/11704236.

APA, 6th edition

Loy, Mina (1882-1966). (["Box 6, folder 162"])(n.d.)["Incident"]. https://collections.library.yale.edu/catalog/11704236.