MLA

Titus, Silius, 1623?-1704. Colonel Titus his address to Oliver Cromwell : prefix'd to a certain treatise, wherein the author (under the borrow'd name of William Allen) proves, that killing the usurper was no murder. 1654]. https://collections.library.yale.edu/catalog/2037398.

APA, 6th edition

Titus, Silius, 1623?-1704. (1654])[Colonel Titus his address to Oliver Cromwell : prefix'd to a certain treatise, wherein the author (under the borrow'd name of William Allen) proves, that killing the usurper was no murder]. https://collections.library.yale.edu/catalog/2037398.