MLA

Co, Panama Pacific International Exposition. The Thirteenth Labor of Hercules. 1914. https://collections.library.yale.edu/catalog/2028606.

APA, 6th edition

Co, P. P. I. E. (1914). The thirteenth labor of Hercules [Covers (Illustrations), Illustrations, Lithographs]. https://collections.library.yale.edu/catalog/2028606.