MLA

William Aitken, MD. Dr. Aitken's Clinical Thermometer. Box 063. 19th century. https://collections.library.yale.edu/catalog/17321488.

APA, 6th edition

William Aitken, MD. (["Box 063"])(19th century)[Dr. Aitken's Clinical Thermometer]. https://collections.library.yale.edu/catalog/17321488.