MLA

FitzGerald, Edward, 1809-1883. Commonplace Book. Box 1, folder +. n.d.. https://collections.library.yale.edu/catalog/2026713.

APA, 6th edition

FitzGerald, Edward, 1809-1883. (["Box 1, folder +"])(n.d.)[Commonplace Book]. https://collections.library.yale.edu/catalog/2026713.