Natural Law Ethics in Theory and PracticeJoseph Boyle, John Liptay, Christopher Tollefsen, Robert P. George · First published 2020Open the Tome
Embrión. Una defensa de la vida humanaRobert. P George, Christopher Tollefsen, Francisco Javier Novo Villaverde · First published 2012Open the Tome
John Paul II's contribution to Catholic bioethicsChristopher Tollefsen · First published 2004Open the Tome