Cite

[Postcard : 1914 January 30, Arnold Ronnebeck and Karl von Freyburg to Marsden Hartley]

MLA

[Postcard : 1914 January 30, Arnold Ronnebeck and Karl Von Freyburg to Marsden Hartley]. 1914. https://collections.library.yale.edu/catalog/11176962.

APA, 6th edition

[Postcard : 1914 January 30, Arnold Ronnebeck and Karl von Freyburg to Marsden Hartley]. (1914). [Correspondence, Postcards]. https://collections.library.yale.edu/catalog/11176962.