Cite

[Postcard] 1920, France, [to Norma Berger]

MLA

Hartley, Marsden, 1877-1943. [Postcard] 1920, France, [to Norma Berger]. Box: Hartley, Marsden to Berger Norma. [1926]. https://collections.library.yale.edu/catalog/2018110.

APA, 6th edition

Hartley, Marsden, 1877-1943. (["Box: Hartley, Marsden to Berger Norma"])([1926])[[Postcard] 1920, France, [to Norma Berger]]. https://collections.library.yale.edu/catalog/2018110.