MLA

Jerome, Saint, -419 or 420. Two letters on eremitic and clerical life. [between 1500 and 1550]. https://collections.library.yale.edu/catalog/9998979.

APA, 6th edition

Jerome, Saint, -419 or 420. ([between 1500 and 1550])[Two letters on eremitic and clerical life]. https://collections.library.yale.edu/catalog/9998979.