Cite

ALS : Weimar?, to Karl Ludwig von Knebel

MLA

Speck, William A. (William Alfred), 1864-1928. ALS : Weimar?, to Karl Ludwig von Knebel. Box 9, folder 285. 1809. https://collections.library.yale.edu/catalog/2005315.

APA, 6th edition

Speck, William A. (William Alfred), 1864-1928. (["Box 9, folder 285"])(1809)[ALS : Weimar?, to Karl Ludwig von Knebel]. https://collections.library.yale.edu/catalog/2005315.