MLA

Ochoa Carrillo, Antonio, 1811-1883. Juárez, Benito. Autograph letter, signed: Chihuahua, to Antonio Ochoa Carrillo. Box 1, folder 38. 1865 July 21. https://collections.library.yale.edu/catalog/32319832.

APA, 6th edition

Ochoa Carrillo, Antonio, 1811-1883. (["Box 1, folder 38"])(1865 July 21)[Juárez, Benito. Autograph letter, signed: Chihuahua, to Antonio Ochoa Carrillo]. https://collections.library.yale.edu/catalog/32319832.