Ornamental Map of the United States & Mexico.
MLA
Ornamental Map of the United States & Mexico. Ensign & Thayer, 1848. https://collections.library.yale.edu/catalog/15603716.
APA, 6th edition
Ornamental Map of the United States & Mexico. (1848). [Maps]. Ensign & Thayer, https://collections.library.yale.edu/catalog/15603716.