Gindorf, Christiane, Anne Steimer, Claus-Michael Lehr, Udo Bock, Stefan Schmitz, and Eleonore Haltner. 2001. “[Marker Transport across Biological Barriers in Vitro: Comparison of Cell Culture Models for the Gastrointestinal Barrier, the Blood-Brain Barrier and the Alveolar Epithelium of the Lung] [Article in German]”. ALTEX - Alternatives to Animal Experimentation 18 (3):155-64. https://altex.org/index.php/altex/article/view/1179.