Cite

Everett, C., autograph letter signed (true copy) to John C. Calhoun

MLA

Wheaton, Joseph, 1755-1828. Everett, C., autograph letter signed (true copy) to John C. Calhoun. Box 1, folder 9. 1823 August 25. https://collections.library.yale.edu/catalog/32528304.

APA, 6th edition

Wheaton, Joseph, 1755-1828. (["Box 1, folder 9"])(1823 August 25)[Everett, C., autograph letter signed (true copy) to John C. Calhoun]. https://collections.library.yale.edu/catalog/32528304.