Cite

ALS : Cassel, to J. F. Schwenke

MLA

Speck, William A. (William Alfred), 1864-1928. ALS : Cassel, to J. F. Schwenke. Box 16, folder 662. 1852 Apr 29. https://collections.library.yale.edu/catalog/17266948.

APA, 6th edition

Speck, William A. (William Alfred), 1864-1928. (["Box 16, folder 662"])(1852 Apr 29)[ALS : Cassel, to J. F. Schwenke]. https://collections.library.yale.edu/catalog/17266948.