Araujo, Robert John, "The UN Declaration on Human Cloning: a survey and assessment of the debate," 7 The National Catholic Bioethics Quarterly 129 – 149 (2007).
Oregon Health & Science University. "Human skin cells converted into embryonic stem cells: First time human stem cells have been produced via nuclear transfer." ScienceDaily. ScienceDaily, ngày 15 tháng 5 năm 2013. .
