Cite

"Wrigley's Spearmint Pepsin Gum."

MLA

Hansen, Bert, 1944-. "Wrigley's Spearmint Pepsin Gum.". Box 12, folder 7. 1911 April 5. https://collections.library.yale.edu/catalog/32326482.

APA, 6th edition

Hansen, Bert, 1944-. (["Box 12, folder 7"])(1911 April 5)["Wrigley's Spearmint Pepsin Gum."]. https://collections.library.yale.edu/catalog/32326482.