MLA

Porter, K. Techniques Porter-Blum Microtome. Yale University School of Medicine, 12AD. https://collections.library.yale.edu/catalog/15817970.

APA, 6th edition

Porter, K. (12 C.E.). Techniques Porter-Blum microtome [Transmission electron micrograph]. Yale University School of Medicine. https://collections.library.yale.edu/catalog/15817970.