Cite

ALS : Zurich, to S.A. Fabrizius

MLA

Speck, William A. (William Alfred), 1864-1928. ALS : Zurich, to S.A. Fabrizius. Box 12, folder 460. 1789 Aug 19. https://collections.library.yale.edu/catalog/17266942.

APA, 6th edition

Speck, William A. (William Alfred), 1864-1928. (["Box 12, folder 460"])(1789 Aug 19)[ALS : Zurich, to S.A. Fabrizius]. https://collections.library.yale.edu/catalog/17266942.