Cite

Painted papier-mâché mask depicting a white duck with a wide bill

MLA

Steinberg, Saul, 1914-1999. Painted papier-mâché mask depicting a white duck with a wide bill. Box 321. undated. https://collections.library.yale.edu/catalog/2016889.

APA, 6th edition

Steinberg, Saul, 1914-1999. (["Box 321"])(undated)[Painted papier-mâché mask depicting a white duck with a wide bill]. https://collections.library.yale.edu/catalog/2016889.