MLA

Ephelia, fl. 1679. A Poem as it was presented to His Sacred Majesty on the discovery of the plott / written by a lady of quality. 1679. https://collections.library.yale.edu/catalog/2018329.

APA, 6th edition

Ephelia, fl. 1679. (1679)[A Poem as it was presented to His Sacred Majesty on the discovery of the plott / written by a lady of quality]. https://collections.library.yale.edu/catalog/2018329.