MLA

Denham, John Charles, -1867. Lawrence, Thomas: graphite sketch of James Boswell; on verso: graphite sketch of four figures. Box 1, folder 70. 1777-1856. https://collections.library.yale.edu/catalog/2067564.

APA, 6th edition

Denham, John Charles, -1867. (["Box 1, folder 70"])(1777-1856)[Lawrence, Thomas: graphite sketch of James Boswell; on verso: graphite sketch of four figures]. https://collections.library.yale.edu/catalog/2067564.