MLA

Ferro, Robert (1941-1988). Holleran, Andrew. Box 1, folder 11-14. 1967-1988, undated. https://collections.library.yale.edu/catalog/17099441.

APA, 6th edition

Ferro, Robert (1941-1988). (["Box 1, folder 11-14"])(1967-1988, undated)[Holleran, Andrew]. https://collections.library.yale.edu/catalog/17099441.