MLA

Luhan, Mabel Dodge, 1879-1962. ----, Trinidad. Box 75, folder 2101. n.d.. https://collections.library.yale.edu/catalog/17085385.

APA, 6th edition

Luhan, Mabel Dodge, 1879-1962. (["Box 75, folder 2101"])(n.d.)[----, Trinidad]. https://collections.library.yale.edu/catalog/17085385.