Cite

Paul Mellon (third from left) and Jules Prown (second from right).

MLA

William B. Carter, Yale Department of Public Information. Paul Mellon (Third from Left) and Jules Prown (Second from Right). 1974. https://collections.library.yale.edu/catalog/10016387.

APA, 6th edition

William B. Carter, Y. D. of P. I. (1974). Paul Mellon (third from left) and Jules Prown (second from right). [Photographic prints]. https://collections.library.yale.edu/catalog/10016387.