Cite

"Slides," draft, holograph, corrected

MLA

Betjeman, John, 1906-1984. "Slides," draft, holograph, corrected. Box 3, folder 203. undated. https://collections.library.yale.edu/catalog/17306199.

APA, 6th edition

Betjeman, John, 1906-1984. (["Box 3, folder 203"])(undated)["Slides," draft, holograph, corrected]. https://collections.library.yale.edu/catalog/17306199.