Bertschinger, Hans U. “[Contribution to the Ethical Appraisal of Xenotransplantation With Respect to Protection of the Dignity of the animals][Article in German]”. ALTEX - Alternatives to Animal Experimentation, vol. 17, no. 1, Feb. 2000, pp. 22-24, https://www.altex.org/index.php/altex/article/view/1410.