Cite

"The walnut is the chief source of income"

MLA

"The Walnut Is the Chief Source of Income". 0AD. https://collections.library.yale.edu/catalog/17265700.

APA, 6th edition

"The walnut is the chief source of income". (0 C.E.). [Photographs (AAT)]. https://collections.library.yale.edu/catalog/17265700.