Township map of Massachusetts, Connecticut and Rhode Island.
MLA
Ensign, Bridgman, and Fanning. Township Map of Massachusetts, Connecticut and Rhode Island. Ensign, Bridgman & Fanning, 1855. https://collections.library.yale.edu/catalog/15606957.
APA, 6th edition
Ensign, B., & F. (1855). Township map of Massachusetts, Connecticut and Rhode Island. [Maps]. Ensign, Bridgman & Fanning, https://collections.library.yale.edu/catalog/15606957.