Groat, P.B.
MLA
Marsh, Othniel Charles, 1831-1899. Groat, P.B.. Box 13, folder 549. 1879. https://collections.library.yale.edu/catalog/32558503.
APA, 6th edition
Marsh, Othniel Charles, 1831-1899. (["Box 13, folder 549"])(1879)[Groat, P.B.]. https://collections.library.yale.edu/catalog/32558503.