Ryffel, Bernhard, Gaetane Woerly, Gabriele Hofmann, Jacqueline Arnold, Brigitte Greiner, and Brian M. J. Foxwell. 1991. “[Discovery of Novel Immunosuppressants in Vitro] [Article in German]”. ALTEX - Alternatives to Animal Experimentation 8 (2):31-38. https://altex.org/index.php/altex/article/view/1837.