MLA

Steinberg, Saul, 1914-1999. Rosa Steinberg's embroidery, lace, and appliqué needlework. Box 343, folder 4728-4731 | Box 541 (Oversize), folder 7290-7291. 1914, undated. https://collections.library.yale.edu/catalog/16698143.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 343, folder 4728-4731 | Box 541 (Oversize), folder 7290-7291"])(1914, undated)[Rosa Steinberg's embroidery, lace, and appliqué needlework]. https://collections.library.yale.edu/catalog/16698143.