MLA

Grant, Vernon, 1902-1990, artist. When a fly wipes his feet on your food he's spreading disease! Never give a germ a break / [graphic]. 1944.. https://collections.library.yale.edu/catalog/16046910.

APA, 6th edition

Grant, Vernon, 1902-1990, artist. (1944.)[When a fly wipes his feet on your food he's spreading disease! Never give a germ a break / [graphic]]. https://collections.library.yale.edu/catalog/16046910.