Circulus Westphalicus, sive Germaniae Inferioris.
MLA
Circulus Westphalicus, Sive Germaniae Inferioris. 0AD. https://collections.library.yale.edu/catalog/15483104.
APA, 6th edition
Circulus Westphalicus, sive Germaniae Inferioris. (0 C.E.). [Maps]. https://collections.library.yale.edu/catalog/15483104.