MLA

Mally, artist. Watch Your Step [Graphic]. National Safety Council, Inc., Chicago, Ill, 0AD. https://collections.library.yale.edu/catalog/16049006.

APA, 6th edition

Mally, artist. (0 C.E.). Watch your step [graphic] [Offset lithographs, Posters]. National Safety Council, Inc., Chicago, Ill. https://collections.library.yale.edu/catalog/16049006.